SCTP: Stream Control Transmission Protocol

layer 4 SCTP

WTF is SCTP

SCTP was created because TCP with its flow control bears too much overhead for modern multimedia protocols. It combines characteristics of UDP and TCP, without head-of-line blocking, to ensure optimal transfer. Error forward correction is included by CRC and flow control is not byte oriented but sequence oriented, being more adapted to multimedia application.

Moreover multi-homing is supported, meaning clients with multiple addresses can be serviced in one stream. Several streams can then be transported in one packet, so less sockets need to be opened as in TCP or UDP. The protocol is not widely spread although being standardized in 2000. And most important, a SCTP socket implementation is missing for programming languages. Nevertheless, it is predominantly used in the regime of telecommunication.

This tutorial will teach you about the configuration of T2 core to activate the SCTP flow stream dissector and give a short introduction to the SCTP plugin.

This is not a tutorial about SCTP, a good overview about the packet structure can be found here: SCTP Note that the tutorial is valid for a version 0.8.13lmw2 and higher.

Preparation

First, restore T2 into a pristine state by removing all unnecessary or older plugins from the plugin folder ~/.tranalyzer/plugins:

t2build -e -y

Are you sure you want to empty the plugin folder '/home/wurst/.tranalyzer/plugins' (y/N)? yes
Plugin folder emptied

Then compile the following plugins:

t2build tranalyzer2 protoStats basicFlow basicStats sctpDecode txtSink

...
BUILD SUCCESSFUL

If you did not create a separate data and results directory yet, please do it now in another bash window, that facilitates your workflow:

mkdir ~/data ~/results

The sample PCAP used in this tutorial can be downloaded here: sctp-multi.pcap.

Please save it in your ~/data folder.

Now you’re all set. Let’s start with the SCTP pcap in T2 default mode.

SCTP in T2 default mode

...
/* ========================================================================== */
/* ------------------------ USER CONFIGURATION FLAGS ------------------------ */
/* ========================================================================== */

#define SCTP_CRCADL32CHK  0 // Checksum computation:
                            //   0: none,
                            //   1: CRC32,
                            //   2: ADLER
#define SCTP_CHNKVAL      0 // 0: chunk type bit field,
                            // 1: chunk type value,
                            // 2: chunk type as string
#define SCTP_CHNKAGGR     0 // Aggregate chunk types, if SCTP_CHNKVAL > 0
#define SCTP_TSNREL       0 // 0: Absolute TSN
                            // 1: Relative TSN
#define SCTP_MAXCTYPE    15 // Maximum chunk types to store/flow, if SCTP_CHNKVAL > 0
#define SCTP_ASMX        10 // Maximum ASCONF IP
#define SCTP_MXADDR       5 // Maximum number of addresses to print in packet mode

/* +++++++++++++++++++++ ENV / RUNTIME - conf Variables +++++++++++++++++++++ */

/*        No env / runtime configuration flags available for sctpDecode       */

/* ========================================================================== */
/* ------------------------- DO NOT EDIT BELOW HERE ------------------------- */
/* ========================================================================== */
...

Invoke t2 with the pcap, store the results it in your ~/results folder and also generate a packet file:

t2 -r ~/data/sctp-multi.pcap -w ~/results/ -s

Only 2 flows. One A and B.

Looking at the plugin end report, a summary of the number of packets and aggregated states is supplied. Two flows are created, so one communication between two peers. A summary of the SCTP statistics and type bitfields is present and can be decoded using tawk -V.

As no sctpStat appears in the end report we have no grave errors, these are the defined bits which can appear:

tawk -V sctpStat

The sctpStat column is to be interpreted as follows:

   bit | sctpStat | Description
   =============================================================================
     0 | 0x01     | Adler32 error
     1 | 0x02     | CRC32 error
     2 | 0x04     | Chunk padded
     3 | 0x08     | Chunk truncated

     4 | 0x10     | 3 Ack
     5 | 0x20     | Type Field overflow
     6 | 0x40     | Do not report
     7 | 0x80     | Stop processing of the packet

But we see these control and type flags:

tawk -V sctpCFlags=0xc7 -V sctpTypeBF=0x0c0f

The sctpCFlags column with value 0xc7 is to be interpreted as follows:

   bit | sctpCFlags | Description
   =============================================================================
     0 | 0x01       | Last segment
     1 | 0x02       | First segment
     2 | 0x04       | Ordered delivery
     6 | 0x40       | Transmission sequence number Error
     7 | 0x80       | Association Sequence Number Error


The sctpTypeBF column with value 0x0c0f is to be interpreted as follows:

   bit | sctpTypeBF | Description
   =============================================================================
     0 | 0x0001     | Payload data
     1 | 0x0002     | Initiation
     2 | 0x0004     | Initiation acknowledgement
     3 | 0x0008     | Selective acknowledgement
    10 | 0x0400     | State cookie
    11 | 0x0800     | Cookie acknowledgement

The Transmission sequence number error can happen, when either packet get lost or swapped. The sctpTypeBF contains the aggregated chunk content types over all flows. So an SCTP flow which is in progress and not terminated yet.

Nevertheless, a quasi normal SCTP stream. Now, open the flow file under your ~/results directory.

tcol ~/results/sctp-multi_flows.txt

%dir  flowInd  flowStat            timeFirst          timeLast           duration  numHdrDesc  numHdrs  hdrDesc        srcMac             dstMac             ethType  ethVlanID  srcIP           srcIPCC  srcIPOrg           srcPort  dstIP           dstIPCC  dstIPOrg           dstPort  l4Proto  numPktsSnt  numPktsRcvd  numBytesSnt  numBytesRcvd  minPktSz  maxPktSz  avePktSize  stdPktSize  minIAT  maxIAT    aveIAT       stdIAT       pktps     bytps     pktAsm  bytAsm        sctpStat  sctpMaxDSNum  sctpPID  sctpVTag    sctpTypeBF  sctpCntD_I_A  sctpCFlags  sctpCCBF  sctpASIP  sctpIS  sctpOS  sctpIARW  sctpIARWMin  sctpIARWMax  sctpARW
A     1        0x0400000001004000  1108716598.686079  1108716598.763435  0.077356  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      37          37           32072        32340         16        1072      866.8108    303.2927    0       0.007658  0.002090703  0.001983343  478.3081  414602.6  0       -0.004160715  0x00      11            0        0x00000eb0  0x040b      60_1_0        0xc7        0x0000              17      17      65535     65535        65535        65535
B     1        0x0400000001004001  1108716598.686375  1108716598.771526  0.085151  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  07       "Private network"  7        192.168.170.8   07       "Private network"  7        132      37          37           32340        32072         4         1072      874.0541    280.4827    0       0.013896  0.002301379  0.003496052  434.5222  379795.9  0       0.004160715   0x00      11            0        0x43232544  0x080d      60_0_0        0xc7        0x0000              17      17      4096      4096         4096         4096

Here are the two flows, but they indicate there are more streams hidden. The maximum announced number of in/out streams (sctpIS and sctpOS) is 17, while the actual data channels (sctpMaxDSNum) is 11. A list of all chunk types can be acquired by invoking the following tawk command:

The packet mode shows all SCTP streams information in one packet aggregated into one column separated by ; (sctpChunkType_Sid_Flags_Len): This column reports chunk type, the stream ID, the chunk flags and the chunk length. We will discuss more about this later

head -n 10 ~/results/sctp-multi_packets.txt | tcol

%pktNo  flowInd  flowStat            time               pktIAT    pktTrip   flowDuration  numHdrs  hdrDesc        ethVlanID  srcMac             dstMac             ethType  srcIP           srcIPCC  srcIPOrg         srcPort  dstIP           dstIPCC  dstIPOrg         dstPort  l4Proto  pktLen  l7Len  sctpVTag    sctpChkSum  sctpChunkType_sid_flags_numDPkts_len_tsn_pid                                          sctpErrType  sctpNChunks  sctpWin  sctpStat  l7Content
1       1        0x0400000001004000  1108716598.686079  0.000000  0.000000  0.000000      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      78      32     0x00000000  0x3761a746  1_0_0x00_0_32_65535_1560164255_110011_                                                0x0000       1            65535    0x00      ... C#%D........\.7......\f......
2       1        0x0400000001004001  1108716598.686375  0.000000  0.000296  0.000000      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      174     128    0x43232544  0xc9018524  2_0_0x00_0_128_4096_13844_110011_                                                     0x0000       1            4096     0x00      ..................6....h..............6.C#%D........\.7................?.'.......v..U...,>|5...............\b...8...\b...\b........
3       1        0x0400000001004000  1108716598.686862  0.000783  0.000487  0.000783      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      150     104    0x00000eb0  0xb85148ea  10_0_0x00_0_104_0_0_0_                                                                0x0000       1            0        0x00      \n..h..............6.C#%D........\.7................?.'.......v..U...,>|5...............\b...8...\b...\b....
4       1        0x0400000001004001  1108716598.687080  0.000705  0.000218  0.000705      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      50      4      0x43232544  0xceec2d79  11_0_0x00_0_4_0_0_0_                                                                  0x0000       1            0        0x00      ....
5       1        0x0400000001004000  1108716598.688291  0.001429  0.001211  0.002212      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      1102    1056   0x00000eb0  0xcfbb0406  0_0_0x07_1_528_0_1560164255_0_;0_1_0x07_2_528_0_1560164256_0_                         0x0000       2            0        0x00      ....\.7.............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................\.7.........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
6       1        0x0400000001004001  1108716598.688538  0.001458  0.000247  0.002163      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      1118    1072   0x43232544  0xce0c78b4  3_0_0x00_0_16_4096_1560164256_0_;0_0_0x07_1_528_0_13844_0_;0_1_0x07_2_528_0_13845_0_  0x0000       3            0        0x00      ....\.7...............6...............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................6.........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
7       1        0x0400000001004000  1108716598.689195  0.000904  0.000657  0.003116      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      1102    1056   0x00000eb0  0xaafc4c8d  0_2_0x07_3_528_0_1560164257_0_;0_3_0x07_4_528_0_1560164258_0_                         0x0000       2            0        0x00      ....\.7.............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................\.7.........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
8       1        0x0400000001004001  1108716598.689402  0.000864  0.000207  0.003027      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      1118    1072   0x43232544  0xe5c3f9f1  3_0_0x00_2_16_4096_1560164258_0_;0_2_0x07_3_528_0_13846_0_;0_3_0x07_4_528_0_13847_0_  0x0000       3            0        0x00      ....\.7...............6...............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................6.........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
9       1        0x0400000001004000  1108716598.690095  0.000900  0.000693  0.004016      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      1102    1056   0x00000eb0  0xd949ce4f  0_4_0x07_5_528_0_1560164259_0_;0_5_0x07_6_528_0_1560164260_0_                         0x0000       2            0        0x00      ....\.7.............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................\.7.........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................

Let’s see what protocols and ports information we have:

lsx sctp-multi_protocols.txt

# Total packets: 74
# Total bytes: 67816 (67.82 K)
# L2/3 Protocol                       Packets                   Bytes       Description
0x0800                           74 [100.00%]         67816 [100.00%]       Internet Protocol version 4 (IPv4)


# Total IPv4 packets: 74 [100.00%]
# Total IPv6 packets: 0 [0.00%]
# L4 Protocol                         Packets                   Bytes       Description
132                              74 [100.00%]         67816 [100.00%]       Stream Control Transmission Protocol


# Total TCP packets: 0 [0.00%]
# Total TCP bytes: 0 [0.00%]


# Total UDP packets: 0 [0.00%]
# Total UDP bytes: 0 [0.00%]

Oups, no layer 4 SCTP packet info? Why??? By default we switched the SCTP statistics in protoStats off, as most users did not need it. So let’s switch it on and rerun t2 without packet mode to save time (If you had a 100 GB pcap, then you would realize the difference :-))

t2conf protoStats -D SCTP_STAT=1 && t2build protoStats

t2 -r ~/data/sctp-multi.pcap -w ~/results/sctp/

Looking into the protocols file note that the SCTP has now an entry for port 7, the Echo protocol, including packet count. Nevertheless, the Description Echo is misleading, as SCTP ports are not compliant with the standard TCP/UDP port designation.

lsx sctp-multi_protocols.txt

# Total packets: 74
# Total bytes: 67816 (67.82 K)
# L2/3 Protocol                       Packets                   Bytes       Description
0x0800                           74 [100.00%]         67816 [100.00%]       Internet Protocol version 4 (IPv4)


# Total IPv4 packets: 74 [100.00%]
# Total IPv6 packets: 0 [0.00%]
# L4 Protocol                         Packets                   Bytes       Description
132                              74 [100.00%]         67816 [100.00%]       Stream Control Transmission Protocol


# Total TCP packets: 0 [0.00%]
# Total TCP bytes: 0 [0.00%]


# Total UDP packets: 0 [0.00%]
# Total UDP bytes: 0 [0.00%]


# Total SCTP packets: 74 [100.00%]
# Total SCTP bytes: 67816 (67.82 K) [100.00%]
# SCTP Port                           Packets                   Bytes       Description
7                                74 [100.00%]         67816 [100.00%]       Echo

Now let’s look what happens when we activate the SCTP dissect mode of T2 core, meaning that we add the SCTP stream ID to the flow hash.

T2 in SCTP stream dissect mode

The anteater has a unique flow concept for SCTP, which dissects the chunk streams and converts them into T2 flows. In order to enable this function the SCTP stream dissect mode has to be enabled via the SCTP_ACTIVATE constant in the core configuration of networkHeaders.h. It is off by default, to optimize performance for the default user.

tranalyzer2

vi src/networkHeaders.h

...
/* ========================================================================== */
/* ------------------------ USER CONFIGURATION FLAGS ------------------------ */
/* ========================================================================== */
...
#define SCTP_ACTIVATE     0 // 0: standard flows
                            // 1: activate SCTP chunk streams -> flows
                            // 2: activate SCTP association -> flows
                            // 3: activate SCTP Chunk & association -> flows
#define SCTP_STATFINDEX   1 // 0: findex increments
                            // 1: findex constant for all SCTP streams in a packet
...
/* ========================================================================== */
/* ------------------------- DO NOT EDIT BELOW HERE ------------------------- */
/* ========================================================================== */
...

SCTP_ACTIVATE has several modes. If set to 1 the chunk stream ID is added to the flow hash, hence each data chunk stream is sorted into one unique flow. Option 2 activates the association mode, thus the verification tag is added to the flow. And in mode 3, both will be added to the flow. Note, that 2 and especially 3 might collide with the port and IP address hash content. So it is advisable to think before what you want to aggregate. E.g. for mode 3 the aggregation of the IP and ports should be switched off via AGGREGATIONFLAG in tranalyzer.h. As they are redundant. In mode 2, if AGGREGATIONFLAG is set to ignore IPs and ports you must be aware that now several flows are aggregated into one SCTP association flow, hence content flags and content itself is aggregated as well. Just to let you know, that the concept is powerful, but you need to know what you want to achieve.

So enable SCTP chunk stream in the core and re-invoke t2 with the -s option.

t2conf tranalyzer2 -D SCTP_ACTIVATE=1 && t2build -R

t2 -r ~/data/sctp-multi.pcap -w ~/results/ -s

Note, in the fourth line SCTP indicates that the core now dissects the protocol and creates independent flows for each SCTP stream.

And now T2 creates 24 flows (12 A flows and 12 B flows) or 12 communication streams.

Move to your results window again and open the ~/results/sctp-multi_flows.txt file. Note that every flow is labeled with the same flowInd (1), as all SCTP stream flows are from one original flow. But sctpDSNum denotes the stream ID, or SCTP Data Stream Number.

tcol ~/results/sctp-multi_flows.txt

%dir  flowInd  flowStat            timeFirst          timeLast           duration  numHdrDesc  numHdrs  hdrDesc        srcMac             dstMac             ethType  ethVlanID  srcIP           srcIPCC  srcIPOrg           srcPort  dstIP           dstIPCC  dstIPOrg           dstPort  l4Proto  numPktsSnt  numPktsRcvd  numBytesSnt  numBytesRcvd  minPktSz  maxPktSz  avePktSize  stdPktSize  minIAT  maxIAT    aveIAT       stdIAT       pktps     bytps     pktAsm      bytAsm     sctpStat  sctpDSNum  sctpPID  sctpVTag    sctpTypeBF  sctpCntD_I_A  sctpCFlags  sctpCCBF  sctpASIP  sctpIS  sctpOS  sctpIARW  sctpIARWMin  sctpIARWMax  sctpARW
A     1        0x0400000001004000  1108716598.697367  1108716598.751383  0.054016  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   -        "-"                7        192.168.170.56  -        "-"                7        132      4           4            2048         2048          512       512       512         0           0       0.019717  0.013504     0.005976828  74.05213  37914.69  0           0          0x00      11         0        0x00000eb0  0x0001      4_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.700651  1108716598.756477  0.055826  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  07       "Private network"  7        192.168.170.8   07       "Private network"  7        132      4           4            2048         2048          512       512       512         0           0       0.022678  0.0139565    0.006462127  71.6512   36685.41  0           0          0x00      11         0        0x43232544  0x0001      4_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.688291  1108716598.751383  0.063092  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   -        "-"                7        192.168.170.56  -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.018223  0.0126184    0.005361295  79.24935  40575.67  0           0          0x00      1          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.688538  1108716598.756477  0.067939  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.023467  0.0135878    0.006479933  73.59544  37680.86  0           0          0x00      1          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.689195  1108716598.752140  0.062945  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.01898   0.012589     0.005557677  79.43443  40670.43  0           0          0x00      2          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.689402  1108716598.756727  0.067325  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.023467  0.013465     0.006579555  74.26662  38024.51  0           0          0x00      2          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.689195  1108716598.753271  0.064076  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.019201  0.0128152    0.005597543  78.03234  39952.56  0           0          0x00      3          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.689402  1108716598.756967  0.067565  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.021079  0.013513     0.00608459   74.00281  37889.44  0           0          0x00      3          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.690095  1108716598.753271  0.063176  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.019201  0.0126352    0.005108401  79.14398  40521.72  0           0          0x00      4          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.693336  1108716598.756967  0.063631  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.021079  0.0127262    0.005697675  78.57806  40231.96  0           0          0x00      4          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.690095  1108716598.760341  0.070246  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.020442  0.0140492    0.005889928  71.17843  36443.36  0           0          0x00      5          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.693336  1108716598.770863  0.077527  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.02454   0.0155054    0.007011673  64.49366  33020.75  0           0          0x00      5          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.693263  1108716598.760341  0.067078  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.020442  0.0134156    0.005683439  74.54008  38164.52  0           0          0x00      6          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.693951  1108716598.770863  0.076912  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.02454   0.0153824    0.006592538  65.00936  33284.79  0           0          0x00      6          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.693263  1108716598.761549  0.068286  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.019427  0.0136572    0.005618318  73.22145  37489.38  0           0          0x00      7          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.693951  1108716598.771163  0.077212  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.024675  0.0154424    0.006634399  64.75677  33155.47  0           0          0x00      7          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.693735  1108716598.761549  0.067814  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   -        "-"                7        192.168.170.56  -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.021395  0.0135628    0.00574128   73.73109  37750.32  0           0          0x00      8          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.694007  1108716598.771163  0.077156  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  07       "Private network"  7        192.168.170.8   07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.024451  0.0154312    0.007122566  64.80377  33179.53  0           0          0x00      8          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.694950  1108716598.762308  0.067358  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.021395  0.0134716    0.005884205  74.23023  38005.88  0           0          0x00      9          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.700250  1108716598.771310  0.071060  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.024598  0.014212     0.007284279  70.36308  36025.89  0           0          0x00      9          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.686079  1108716598.763435  0.077356  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      24          41           18776        34356         16        1072      782.3333    347.4483    0       0.008278  0.003223167  0.002523227  310.2539  242722    -0.2615385  -0.293232  0x00      0          0        0x00000eb0  0x040b      6_1_0         0xc7        0x0000              17      17      65535     65535        65535        65535
B     1        0x0400000001004001  1108716598.686375  1108716598.771526  0.085151  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  07       "Private network"  7        192.168.170.8   07       "Private network"  7        132      41          24           34356        18776         4         1072      837.9512    288.5713    0       0.013896  0.002076854  0.003394506  481.4976  403471.5  0.2615385   0.293232   0x00      0          0        0x43232544  0x080d      6_0_0         0xc7        0x0000              17      17      4096      4096         4096         4096
A     1        0x0400000001004000  1108716598.694950  1108716598.763435  0.068485  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.022134  0.013697     0.005530534  73.00869  37380.45  0           0          0x00      10         0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.700597  1108716598.771526  0.070929  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.022732  0.0141858    0.005774313  70.49303  36092.43  0           0          0x00      10         0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0

If you look at the packets file you will see that the flowInd is always 1 and there are several packet numbers with the same pktNo. Now every chunk has its own packet line and thus is easier to post process. Moreover all T2 plugins can now operate on SCTP packets/flows like in other protocols e.g. TCP and selection by tawk according to flows and streams is facilitated.

head -n 10 ~/results/sctp-multi_packets.txt | tcol

%pktNo  flowInd  flowStat            time               pktIAT    pktTrip   flowDuration  numHdrs  hdrDesc        ethVlanID  srcMac             dstMac             ethType  srcIP           srcIPCC  srcIPOrg         srcPort  dstIP           dstIPCC  dstIPOrg         dstPort  l4Proto  pktLen  l7Len  sctpVTag    sctpChkSum  sctpChunkType_sid_flags_numDPkts_len_tsn_pid  sctpErrType  sctpNChunks  sctpWin  sctpStat  l7Content
1       1        0x0400000001004000  1108716598.686079  0.000000  0.000000  0.000000      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      78      32     0x00000000  0x3761a746  1_0_0x00_0_32_65535_1560164255_110011_        0x0000       1            65535    0x00
2       1        0x0400000001004001  1108716598.686375  0.000000  0.000296  0.000000      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      174     128    0x43232544  0xc9018524  2_0_0x00_0_128_4096_13844_110011_             0x0000       1            4096     0x00
3       1        0x0400000001004000  1108716598.686862  0.000783  0.000487  0.000783      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      150     104    0x00000eb0  0xb85148ea  10_0_0x00_0_104_0_0_0_                        0x0000       1            0        0x00
4       1        0x0400000001004001  1108716598.687080  0.000705  0.000218  0.000705      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      50      4      0x43232544  0xceec2d79  11_0_0x00_0_4_0_0_0_                          0x0000       1            0        0x00
5       1        0x0400000001004000  1108716598.688291  0.001429  0.001211  0.002212      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      1102    512    0x00000eb0  0xcfbb0406  0_0_0x07_1_528_0_1560164255_0_                0x0000       1            0        0x00      ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
5       1        0x0400000001004000  1108716598.688291  0.000000  0.000000  0.000000      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   -        -                7        192.168.170.56  -        -                7        132      1102    512    0x00000eb0  0xcfbb0406  0_1_0x07_1_528_0_1560164256_0_                0x0000       1            0        0x00      ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
6       1        0x0400000001004001  1108716598.688538  0.001458  0.000247  0.002163      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      1118    1072   0x43232544  0xce0c78b4  3_0_0x00_0_16_4096_1560164256_0_              0x0000       1            4096     0x00
6       1        0x0400000001004001  1108716598.688538  0.000000  0.000247  0.002163      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      1118    512    0x43232544  0xce0c78b4  0_0_0x07_1_528_0_13844_0_                     0x0000       1            0        0x00      ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
6       1        0x0400000001004001  1108716598.688538  0.000000  0.000247  0.000000      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  -        -                7        192.168.170.8   -        -                7        132      1118    512    0x43232544  0xce0c78b4  0_1_0x07_1_528_0_13845_0_                     0x0000       1            0        0x00      ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................

If you like every stream flow to be labelled with a separate index, then disable SCTP_STATFINDEX, recompile and rerun t2:

t2conf tranalyzer2 -D SCTP_STATFINDEX=0 && t2build -R

t2 -r ~/data/sctp-multi.pcap -w ~/results/ -s

Now each flow stream has a different flowInd. So you can easily discern which packet belongs to which stream flow by the flowInd alone, unless there are more packets. Nevertheless, if there are more flows of any protocol present to you, the flowInd to packet relation is then unique but difficult to extract. If you want to treat streams individually independent of packet flow association, this is the mode of choice.

tcol ~/results/sctp-multi_flows.txt

%dir  flowInd  flowStat            timeFirst          timeLast           duration  numHdrDesc  numHdrs  hdrDesc        srcMac             dstMac             ethType  ethVlanID  srcIP           srcIPCC  srcIPOrg           srcPort  dstIP           dstIPCC  dstIPOrg           dstPort  l4Proto  numPktsSnt  numPktsRcvd  numBytesSnt  numBytesRcvd  minPktSz  maxPktSz  avePktSize  stdPktSize  minIAT  maxIAT    aveIAT       stdIAT       pktps     bytps     pktAsm      bytAsm     sctpStat  sctpDSNum  sctpPID  sctpVTag    sctpTypeBF  sctpCntD_I_A  sctpCFlags  sctpCCBF  sctpASIP  sctpIS  sctpOS  sctpIARW  sctpIARWMin  sctpIARWMax  sctpARW
A     12       0x0400000001004000  1108716598.697367  1108716598.751383  0.054016  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   -        "-"                7        192.168.170.56  -        "-"                7        132      4           4            2048         2048          512       512       512         0           0       0.019717  0.013504     0.005976828  74.05213  37914.69  0           0          0x00      11         0        0x00000eb0  0x0001      4_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     12       0x0400000001004001  1108716598.700651  1108716598.756477  0.055826  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  07       "Private network"  7        192.168.170.8   07       "Private network"  7        132      4           4            2048         2048          512       512       512         0           0       0.022678  0.0139565    0.006462127  71.6512   36685.41  0           0          0x00      11         0        0x43232544  0x0001      4_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     2        0x0400000001004000  1108716598.688291  1108716598.751383  0.063092  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   -        "-"                7        192.168.170.56  -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.018223  0.0126184    0.005361295  79.24935  40575.67  0           0          0x00      1          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     2        0x0400000001004001  1108716598.688538  1108716598.756477  0.067939  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.023467  0.0135878    0.006479933  73.59544  37680.86  0           0          0x00      1          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     3        0x0400000001004000  1108716598.689195  1108716598.752140  0.062945  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.01898   0.012589     0.005557677  79.43443  40670.43  0           0          0x00      2          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     3        0x0400000001004001  1108716598.689402  1108716598.756727  0.067325  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.023467  0.013465     0.006579555  74.26662  38024.51  0           0          0x00      2          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     4        0x0400000001004000  1108716598.689195  1108716598.753271  0.064076  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.019201  0.0128152    0.005597543  78.03234  39952.56  0           0          0x00      3          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     4        0x0400000001004001  1108716598.689402  1108716598.756967  0.067565  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.021079  0.013513     0.00608459   74.00281  37889.44  0           0          0x00      3          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     5        0x0400000001004000  1108716598.690095  1108716598.753271  0.063176  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.019201  0.0126352    0.005108401  79.14398  40521.72  0           0          0x00      4          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     5        0x0400000001004001  1108716598.693336  1108716598.756967  0.063631  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.021079  0.0127262    0.005697675  78.57806  40231.96  0           0          0x00      4          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     6        0x0400000001004000  1108716598.690095  1108716598.760341  0.070246  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.020442  0.0140492    0.005889928  71.17843  36443.36  0           0          0x00      5          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     6        0x0400000001004001  1108716598.693336  1108716598.770863  0.077527  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.02454   0.0155054    0.007011673  64.49366  33020.75  0           0          0x00      5          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     7        0x0400000001004000  1108716598.693263  1108716598.760341  0.067078  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.020442  0.0134156    0.005683439  74.54008  38164.52  0           0          0x00      6          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     7        0x0400000001004001  1108716598.693951  1108716598.770863  0.076912  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.02454   0.0153824    0.006592538  65.00936  33284.79  0           0          0x00      6          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     8        0x0400000001004000  1108716598.693263  1108716598.761549  0.068286  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.019427  0.0136572    0.005618318  73.22145  37489.38  0           0          0x00      7          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     8        0x0400000001004001  1108716598.693951  1108716598.771163  0.077212  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.024675  0.0154424    0.006634399  64.75677  33155.47  0           0          0x00      7          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     9        0x0400000001004000  1108716598.693735  1108716598.761549  0.067814  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   -        "-"                7        192.168.170.56  -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.021395  0.0135628    0.00574128   73.73109  37750.32  0           0          0x00      8          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     9        0x0400000001004001  1108716598.694007  1108716598.771163  0.077156  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  07       "Private network"  7        192.168.170.8   07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.024451  0.0154312    0.007122566  64.80377  33179.53  0           0          0x00      8          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     10       0x0400000001004000  1108716598.694950  1108716598.762308  0.067358  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.021395  0.0134716    0.005884205  74.23023  38005.88  0           0          0x00      9          0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     10       0x0400000001004001  1108716598.700250  1108716598.771310  0.071060  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.024598  0.014212     0.007284279  70.36308  36025.89  0           0          0x00      9          0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.686079  1108716598.763435  0.077356  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      24          41           18776        34356         16        1072      782.3333    347.4483    0       0.008278  0.003223167  0.002523227  310.2539  242722    -0.2615385  -0.293232  0x00      0          0        0x00000eb0  0x040b      6_1_0         0xc7        0x0000              17      17      65535     65535        65535        65535
B     1        0x0400000001004001  1108716598.686375  1108716598.771526  0.085151  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  07       "Private network"  7        192.168.170.8   07       "Private network"  7        132      41          24           34356        18776         4         1072      837.9512    288.5713    0       0.013896  0.002076854  0.003394506  481.4976  403471.5  0.2615385   0.293232   0x00      0          0        0x43232544  0x080d      6_0_0         0xc7        0x0000              17      17      4096      4096         4096         4096
A     11       0x0400000001004000  1108716598.694950  1108716598.763435  0.068485  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.022134  0.013697     0.005530534  73.00869  37380.45  0           0          0x00      10         0        0x00000eb0  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     11       0x0400000001004001  1108716598.700597  1108716598.771526  0.070929  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.022732  0.0141858    0.005774313  70.49303  36092.43  0           0          0x00      10         0        0x43232544  0x0001      5_0_0         0x47        0x0000              0       0       0         4294967295   0            0

Now each flow owns an extra flowInd. Same for the packets.

head -n 10 ~/results/sctp-multi_packets.txt | tcol

%pktNo  flowInd  flowStat            time               pktIAT    pktTrip   flowDuration  numHdrs  hdrDesc        ethVlanID  srcMac             dstMac             ethType  srcIP           srcIPCC  srcIPOrg         srcPort  dstIP           dstIPCC  dstIPOrg         dstPort  l4Proto  pktLen  l7Len  sctpVTag    sctpChkSum  sctpChunkType_sid_flags_numDPkts_len_tsn_pid  sctpErrType  sctpNChunks  sctpWin  sctpStat  l7Content
1       1        0x0400000001004000  1108716598.686079  0.000000  0.000000  0.000000      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      78      32     0x00000000  0x3761a746  1_0_0x00_0_32_65535_1560164255_110011_        0x0000       1            65535    0x00
2       1        0x0400000001004001  1108716598.686375  0.000000  0.000296  0.000000      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      174     128    0x43232544  0xc9018524  2_0_0x00_0_128_4096_13844_110011_             0x0000       1            4096     0x00
3       1        0x0400000001004000  1108716598.686862  0.000783  0.000487  0.000783      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      150     104    0x00000eb0  0xb85148ea  10_0_0x00_0_104_0_0_0_                        0x0000       1            0        0x00
4       1        0x0400000001004001  1108716598.687080  0.000705  0.000218  0.000705      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      50      4      0x43232544  0xceec2d79  11_0_0x00_0_4_0_0_0_                          0x0000       1            0        0x00
5       1        0x0400000001004000  1108716598.688291  0.001429  0.001211  0.002212      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      1102    512    0x00000eb0  0xcfbb0406  0_0_0x07_1_528_0_1560164255_0_                0x0000       1            0        0x00      ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
5       2        0x0400000001004000  1108716598.688291  0.000000  0.000000  0.000000      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   -        -                7        192.168.170.56  -        -                7        132      1102    512    0x00000eb0  0xcfbb0406  0_1_0x07_1_528_0_1560164256_0_                0x0000       1            0        0x00      ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
6       1        0x0400000001004001  1108716598.688538  0.001458  0.000247  0.002163      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      1118    1072   0x43232544  0xce0c78b4  3_0_0x00_0_16_4096_1560164256_0_              0x0000       1            4096     0x00
6       1        0x0400000001004001  1108716598.688538  0.000000  0.000247  0.002163      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      1118    512    0x43232544  0xce0c78b4  0_0_0x07_1_528_0_13844_0_                     0x0000       1            0        0x00      ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
6       2        0x0400000001004001  1108716598.688538  0.000000  0.000247  0.000000      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  -        -                7        192.168.170.8   -        -                7        132      1118    512    0x43232544  0xce0c78b4  0_1_0x07_1_528_0_13845_0_                     0x0000       1            0        0x00      ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................

Now the packet numbers can be assigned also to the flow stream directly, they match now sctpChunk_Sid + 1 in this special case. If there are more flows around, this is not the case. Nevertheless, if you extracted a SCTP connection consisting of many streams, this mode considerably facilitates the post processing with tawk:

head -n 10 ~/results/sctp-multi_packets.txt | tcol

%pktNo  flowInd  flowStat            time               pktIAT    pktTrip   flowDuration  numHdrs  hdrDesc        ethVlanID  srcMac             dstMac             ethType  srcIP           srcIPCC  srcIPOrg         srcPort  dstIP           dstIPCC  dstIPOrg         dstPort  l4Proto  pktLen  l7Len  sctpVTag    sctpChunkType_sid_flags_numDPkts_len_tsn_pid  sctpNChunks  sctpWin  sctpStat  l7Content
1       1        0x0400000001004000  1108716598.686079  0.000000  0.000000  0.000000      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      78      32     0x00000000  1_0_0x00_0_32_1560164255_110011_              1            65535    0x00
2       1        0x0400000001004001  1108716598.686375  0.000000  0.000296  0.000000      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      174     128    0x43232544  2_0_0x00_0_128_13844_110011_                  1            4096     0x00
3       1        0x0400000001004000  1108716598.686862  0.000783  0.000487  0.000783      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      150     104    0x00000eb0  10_0_0x00_0_104_0_0_                          1            0        0x00
4       1        0x0400000001004001  1108716598.687080  0.000705  0.000218  0.000705      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      50      4      0x43232544  11_0_0x00_0_4_0_0_                            1            0        0x00
5       1        0x0400000001004000  1108716598.688291  0.001429  0.001211  0.002212      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      1102    512    0x00000eb0  0_0_0x07_1_528_1560164255_0_                  1            0        0x00      ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
5       2        0x0400000001004000  1108716598.688291  0.000000  0.000000  0.000000      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   -        -                7        192.168.170.56  -        -                7        132      1102    512    0x00000eb0  0_1_0x07_1_528_1560164256_0_                  1            0        0x00      ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
6       1        0x0400000001004001  1108716598.688538  0.001458  0.000247  0.002163      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      1118    1072   0x43232544  3_0_0x00_0_16_1560164256_0_                   1            4096     0x00
6       1        0x0400000001004001  1108716598.688538  0.000000  0.000247  0.002163      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      1118    512    0x43232544  0_0_0x07_1_528_13844_0_                       1            0        0x00      ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
6       2        0x0400000001004001  1108716598.688538  0.000000  0.000247  0.000000      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  -        -                7        192.168.170.8   -        -                7        132      1118    512    0x43232544  0_1_0x07_1_528_13845_0_                       1            0        0x00      ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................

Note that different flowInd can originate from the same packet and now different streams in a packet have the same packet number, e.g. pktNo = 5.

Now lets try the SCTP association -> flows mode which aggregates all packets of an SCTP association into one flow, iff the default 4 tuple aggregation IPs and ports is disabled, the protocol is used to segregate the SCTP flows from all other protocols. See the Flexible Flow Aggregation tutorial.

So enable SCTP mode 2 and mask the IPs and the upper range or the ports, as the lower is default 1, then recompile and rerun t2 on the pcap.

t2conf tranalyzer2 -D SCTP_ACTIVATE=2 -D AGGREGATIONFLAG=0x1e -D SRCIP4CMSK=0 -D DSTIP4CMSK=0 -D SRCPORTHW=65535 -D DSTPORTHW=65535 && t2build -R

t2 -r ~/data/sctp-multi.pcap -w ~/results/sctp/sctp-multi -s

Note that basicStats only sees the network, as the mask is now /0, the ports are all aggregated in one flow and only the SCTP association counts. So we expect 2 flows, but we see 3, why?

tcol ~/results/sctp-multi_flows.txt

%dir  flowInd  flowStat            timeFirst          timeLast           duration  numHdrDesc  numHdrs  hdrDesc        srcMac             dstMac             ethType  ethVlanID  srcIP    srcIPCC  srcIPOrg  srcPort  dstIP    dstIPCC  dstIPOrg  dstPort  l4Proto  numPktsSnt  numPktsRcvd  numBytesSnt  numBytesRcvd  minPktSz  maxPktSz  avePktSize  stdPktSize  minIAT  maxIAT    aveIAT        stdIAT       pktps     bytps     pktAsm  bytAsm  sctpStat  sctpDSNum  sctpPID  sctpVTag    sctpTypeBF  sctpCntD_I_A  sctpCFlags  sctpCCBF  sctpASIP  sctpIS  sctpOS  sctpIARW  sctpIARWMin  sctpIARWMax  sctpARW
A     1        0x0400000001004000  1108716598.686079  1108716598.686079  0.000000  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              0.0.0.0  -        "-"       1        0.0.0.0  -        "-"       1        132      1           0            32           0             32        32        32          0           0       0         0             0            0         0         1       1       0x00      0          0        0x00000000  0x0002      0_1_0         0x00        0x0000              17      17      65535     65535        65535        65535
A     3        0x0400000001004000  1108716598.686862  1108716598.763435  0.076573  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              0.0.0.0  -        "-"       1        0.0.0.0  -        "-"       1        132      77          0            46392        0             16        1072      602.4935    227.7843    0       0.007658  0.0009944546  0.001732412  1005.576  605853.2  1       1       0x00      11         0        0x00000eb0  0x0409      60_0_0        0xc7        0x0000              0       0       0         65535        65535        65317.21
A     2        0x0400000001004000  1108716598.686375  1108716598.771526  0.085151  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              0.0.0.0  -        "-"       1        0.0.0.0  -        "-"       1        132      95          0            62004        0             4         1072      652.6737    249.8183    0       0.013896  0.0008963263  0.00247492   1115.665  728165.2  1       1       0x00      11         0        0x43232544  0x080d      60_0_0        0xc7        0x0000              17      17      4096      4096         4096         4096

Ahhh, the first flow contains the SCTP_CT_INIT packet where the verification tag is 0. Oups.

If you switch now to mode 3 then the result is the same as with mode 1, except when more IP streams are involved, but I do not have traffic for that, which I can publish.

t2conf tranalyzer2 -D SCTP_ACTIVATE=3 && t2build -R

t2 -r ~/data/sctp-multi.pcap -w ~/results/sctp/sctp-multi -s

...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Number of processed   flows: 25
Number of processed A flows: 25 [100.00%]
Number of request     flows: 25 [100.00%]
Total   A/B    flow asymmetry: 1.00
Total req/rply flow asymmetry: 1.00
...

Then you have 25 instead of 24, for the same reasons. This is experimental, so have patience or give us hints how to improve the anteater.

Now we look into the plugin sctpDecode, which dissects more the chunk information, also currently experimental and programmed according to my needs, so please comment.

sctpDecode

This plugin was designed for a troubleshooting job we had to do at a customer. I will add more in due time, or please give feedback to the anteater email. Then, your request will be integrated.

So what can be configured? Move to the sctpDecode/src directory and open sctpDecode.h.

sctpDecode

vi src/sctpDecode.h

...
/* ========================================================================== */
/* ------------------------ USER CONFIGURATION FLAGS ------------------------ */
/* ========================================================================== */

#define SCTP_CRCADL32CHK 0 // compute 1: CRC32 checksum, 2: ADLER checksum
#define SCTP_CHNKVAL     0 // 0: chunk type bit field,
                           // 1: chunk type value,
                           // 2: chunk type as string
#define SCTP_CHNKAGGR    0 // Aggregate chunk types, if SCTP_CHNKVAL > 0
#define SCTP_MAXCTYPE   15 // maximum chunk types to store/flow, if SCTP_CHNKVAL > 0
#define SCTP_ASMX       10 // maximum ASCONF IP
#define SCTP_MXADDR      5 // maximum

/* ========================================================================== */
/* ------------------------- DO NOT EDIT BELOW HERE ------------------------- */
/* ========================================================================== */
...

The plugin computes the different checksums in use, either CRC32 or Adler. By default they are disabled, because it adds unnecessary load if somebody is not interested in that.

Switch on CRC32 as our pcap uses CRC32. Also reset SCTP_STATFINDEX to 1 via t2conf, recompile all and rerun t2 using again also the -s packet option.

t2conf tranalyzer2 -D SCTP_STATFINDEX=1

t2conf sctpDecode -D SCTP_CRCADL32CHK=1 -D SCTP_CHNKVAL=1

t2build -R

t2 -r ~/data/sctp-multi.pcap -w ~/results/sctp/ -s

...
--------------------------------------------------------------------------------
basicStats: Biggest L3 talker: 192.168.170.56: 41 [55.41%] packets
basicStats: Biggest L3 talker: 192.168.170.56: 39074 (39.07 K) [57.62%] bytes
sctpDecode: aggregated sctpCFlags=0xc7
--------------------------------------------------------------------------------
...

The status reports that there are no checksum errors in sctpStat. But there are communication errors regarding sequence and association numbers. We had them earlier in the end report remember?

tawk -V sctpCFlags=0xc7

The sctpCFlags column with value 0xc7 is to be interpreted as follows:

   bit | sctpCFlags | Description
   =============================================================================
     0 | 0x01       | Last segment
     1 | 0x02       | First segment
     2 | 0x04       | Ordered delivery
     6 | 0x40       | Transmission sequence number Error
     7 | 0x80       | Association Sequence Number Error

Also the SCTP type bitfield in the end report is gone, because now we list the explicit types in the flow file. If you look into the flow file, you will note that the bitfield is now replaced by the sctpType column listing all unique appearing SCTP stream types separated by ;.

tcol ~/results/sctp-multi_flows.txt

%dir  flowInd  flowStat            timeFirst          timeLast           duration  numHdrDesc  numHdrs  hdrDesc        srcMac             dstMac             ethType  ethVlanID  srcIP           srcIPCC  srcIPOrg           srcPort  dstIP           dstIPCC  dstIPOrg           dstPort  l4Proto  numPktsSnt  numPktsRcvd  numBytesSnt  numBytesRcvd  minPktSz  maxPktSz  avePktSize  stdPktSize  minIAT  maxIAT    aveIAT       stdIAT       pktps     bytps     pktAsm      bytAsm     sctpStat  sctpDSNum  sctpPID  sctpVTag    sctpType  sctpCntD_I_A  sctpCFlags  sctpCCBF  sctpASIP  sctpIS  sctpOS  sctpIARW  sctpIARWMin  sctpIARWMax  sctpARW
A     1        0x0400000001004000  1108716598.697367  1108716598.751383  0.054016  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   -        "-"                7        192.168.170.56  -        "-"                7        132      4           4            2048         2048          512       512       512         0           0       0.019717  0.013504     0.005976828  74.05213  37914.69  0           0          0x00      11         0        0x00000eb0  0         4_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.700651  1108716598.756477  0.055826  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  07       "Private network"  7        192.168.170.8   07       "Private network"  7        132      4           4            2048         2048          512       512       512         0           0       0.022678  0.0139565    0.006462127  71.6512   36685.41  0           0          0x00      11         0        0x43232544  0         4_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.688291  1108716598.751383  0.063092  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   -        "-"                7        192.168.170.56  -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.018223  0.0126184    0.005361295  79.24935  40575.67  0           0          0x00      1          0        0x00000eb0  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.688538  1108716598.756477  0.067939  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.023467  0.0135878    0.006479933  73.59544  37680.86  0           0          0x00      1          0        0x43232544  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.689195  1108716598.752140  0.062945  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.01898   0.012589     0.005557677  79.43443  40670.43  0           0          0x00      2          0        0x00000eb0  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.689402  1108716598.756727  0.067325  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.023467  0.013465     0.006579555  74.26662  38024.51  0           0          0x00      2          0        0x43232544  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.689195  1108716598.753271  0.064076  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.019201  0.0128152    0.005597543  78.03234  39952.56  0           0          0x00      3          0        0x00000eb0  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.689402  1108716598.756967  0.067565  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.021079  0.013513     0.00608459   74.00281  37889.44  0           0          0x00      3          0        0x43232544  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.690095  1108716598.753271  0.063176  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.019201  0.0126352    0.005108401  79.14398  40521.72  0           0          0x00      4          0        0x00000eb0  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.693336  1108716598.756967  0.063631  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.021079  0.0127262    0.005697675  78.57806  40231.96  0           0          0x00      4          0        0x43232544  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.690095  1108716598.760341  0.070246  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.020442  0.0140492    0.005889928  71.17843  36443.36  0           0          0x00      5          0        0x00000eb0  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.693336  1108716598.770863  0.077527  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.02454   0.0155054    0.007011673  64.49366  33020.75  0           0          0x00      5          0        0x43232544  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.693263  1108716598.760341  0.067078  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.020442  0.0134156    0.005683439  74.54008  38164.52  0           0          0x00      6          0        0x00000eb0  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.693951  1108716598.770863  0.076912  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.02454   0.0153824    0.006592538  65.00936  33284.79  0           0          0x00      6          0        0x43232544  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.693263  1108716598.761549  0.068286  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.019427  0.0136572    0.005618318  73.22145  37489.38  0           0          0x00      7          0        0x00000eb0  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.693951  1108716598.771163  0.077212  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.024675  0.0154424    0.006634399  64.75677  33155.47  0           0          0x00      7          0        0x43232544  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.693735  1108716598.761549  0.067814  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   -        "-"                7        192.168.170.56  -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.021395  0.0135628    0.00574128   73.73109  37750.32  0           0          0x00      8          0        0x00000eb0  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.694007  1108716598.771163  0.077156  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  07       "Private network"  7        192.168.170.8   07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.024451  0.0154312    0.007122566  64.80377  33179.53  0           0          0x00      8          0        0x43232544  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.694950  1108716598.762308  0.067358  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.021395  0.0134716    0.005884205  74.23023  38005.88  0           0          0x00      9          0        0x00000eb0  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.700250  1108716598.771310  0.071060  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.024598  0.014212     0.007284279  70.36308  36025.89  0           0          0x00      9          0        0x43232544  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.686079  1108716598.763435  0.077356  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      24          41           18776        34356         16        1072      782.3333    347.4483    0       0.008278  0.003223167  0.002523227  310.2539  242722    -0.2615385  -0.293232  0x00      0          0        0x00000eb0  1;10;0;3  6_1_0         0xc7        0x0000              17      17      65535     65535        65535        65535
B     1        0x0400000001004001  1108716598.686375  1108716598.771526  0.085151  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  07       "Private network"  7        192.168.170.8   07       "Private network"  7        132      41          24           34356        18776         4         1072      837.9512    288.5713    0       0.013896  0.002076854  0.003394506  481.4976  403471.5  0.2615385   0.293232   0x00      0          0        0x43232544  2;11;3;0  6_0_0         0xc7        0x0000              17      17      4096      4096         4096         4096
A     1        0x0400000001004000  1108716598.694950  1108716598.763435  0.068485  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.022134  0.013697     0.005530534  73.00869  37380.45  0           0          0x00      10         0        0x00000eb0  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.700597  1108716598.771526  0.070929  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.022732  0.0141858    0.005774313  70.49303  36092.43  0           0          0x00      10         0        0x43232544  0         5_0_0         0x47        0x0000              0       0       0         4294967295   0            0

Same happens to the packet file, so we go directly to the human readable config. If you like a human readable output set SCTP_CHNKVAL to 2, recompile sctpDecode and rerun t2.

t2conf sctpDecode -D SCTP_CHNKVAL=2 && t2build sctpDecode

t2 -r ~/data/sctp-multi.pcap -w ~/results/sctp/sctp-multi -s

Now the type is human readable.

tcol ~/results/sctp-multi_flows.txt

%dir  flowInd  flowStat            timeFirst          timeLast           duration  numHdrDesc  numHdrs  hdrDesc        srcMac             dstMac             ethType  ethVlanID  srcIP           srcIPCC  srcIPOrg           srcPort  dstIP           dstIPCC  dstIPOrg           dstPort  l4Proto  numPktsSnt  numPktsRcvd  numBytesSnt  numBytesRcvd  minPktSz  maxPktSz  avePktSize  stdPktSize  minIAT  maxIAT    aveIAT       stdIAT       pktps     bytps     pktAsm      bytAsm     sctpStat  sctpDSNum  sctpPID  sctpVTag    sctpTypeN                      sctpCntD_I_A  sctpCFlags  sctpCCBF  sctpASIP  sctpIS  sctpOS  sctpIARW  sctpIARWMin  sctpIARWMax  sctpARW
A     1        0x0400000001004000  1108716598.697367  1108716598.751383  0.054016  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   -        "-"                7        192.168.170.56  -        "-"                7        132      4           4            2048         2048          512       512       512         0           0       0.019717  0.013504     0.005976828  74.05213  37914.69  0           0          0x00      11         0        0x00000eb0  DATA                           4_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.700651  1108716598.756477  0.055826  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  07       "Private network"  7        192.168.170.8   07       "Private network"  7        132      4           4            2048         2048          512       512       512         0           0       0.022678  0.0139565    0.006462127  71.6512   36685.41  0           0          0x00      11         0        0x43232544  DATA                           4_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.688291  1108716598.751383  0.063092  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   -        "-"                7        192.168.170.56  -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.018223  0.0126184    0.005361295  79.24935  40575.67  0           0          0x00      1          0        0x00000eb0  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.688538  1108716598.756477  0.067939  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.023467  0.0135878    0.006479933  73.59544  37680.86  0           0          0x00      1          0        0x43232544  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.689195  1108716598.752140  0.062945  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.01898   0.012589     0.005557677  79.43443  40670.43  0           0          0x00      2          0        0x00000eb0  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.689402  1108716598.756727  0.067325  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.023467  0.013465     0.006579555  74.26662  38024.51  0           0          0x00      2          0        0x43232544  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.689195  1108716598.753271  0.064076  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.019201  0.0128152    0.005597543  78.03234  39952.56  0           0          0x00      3          0        0x00000eb0  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.689402  1108716598.756967  0.067565  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.021079  0.013513     0.00608459   74.00281  37889.44  0           0          0x00      3          0        0x43232544  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.690095  1108716598.753271  0.063176  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.019201  0.0126352    0.005108401  79.14398  40521.72  0           0          0x00      4          0        0x00000eb0  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.693336  1108716598.756967  0.063631  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.021079  0.0127262    0.005697675  78.57806  40231.96  0           0          0x00      4          0        0x43232544  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.690095  1108716598.760341  0.070246  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.020442  0.0140492    0.005889928  71.17843  36443.36  0           0          0x00      5          0        0x00000eb0  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.693336  1108716598.770863  0.077527  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.02454   0.0155054    0.007011673  64.49366  33020.75  0           0          0x00      5          0        0x43232544  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.693263  1108716598.760341  0.067078  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.020442  0.0134156    0.005683439  74.54008  38164.52  0           0          0x00      6          0        0x00000eb0  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.693951  1108716598.770863  0.076912  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.02454   0.0153824    0.006592538  65.00936  33284.79  0           0          0x00      6          0        0x43232544  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.693263  1108716598.761549  0.068286  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.019427  0.0136572    0.005618318  73.22145  37489.38  0           0          0x00      7          0        0x00000eb0  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.693951  1108716598.771163  0.077212  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.024675  0.0154424    0.006634399  64.75677  33155.47  0           0          0x00      7          0        0x43232544  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.693735  1108716598.761549  0.067814  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   -        "-"                7        192.168.170.56  -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.021395  0.0135628    0.00574128   73.73109  37750.32  0           0          0x00      8          0        0x00000eb0  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.694007  1108716598.771163  0.077156  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  07       "Private network"  7        192.168.170.8   07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.024451  0.0154312    0.007122566  64.80377  33179.53  0           0          0x00      8          0        0x43232544  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.694950  1108716598.762308  0.067358  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.021395  0.0134716    0.005884205  74.23023  38005.88  0           0          0x00      9          0        0x00000eb0  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.700250  1108716598.771310  0.071060  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.024598  0.014212     0.007284279  70.36308  36025.89  0           0          0x00      9          0        0x43232544  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
A     1        0x0400000001004000  1108716598.686079  1108716598.763435  0.077356  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      24          41           18776        34356         16        1072      782.3333    347.4483    0       0.008278  0.003223167  0.002523227  310.2539  242722    -0.2615385  -0.293232  0x00      0          0        0x00000eb0  INIT;COOKIE-ECHO;DATA;SACK     6_1_0         0xc7        0x0000              17      17      65535     65535        65535        65535
B     1        0x0400000001004001  1108716598.686375  1108716598.771526  0.085151  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  07       "Private network"  7        192.168.170.8   07       "Private network"  7        132      41          24           34356        18776         4         1072      837.9512    288.5713    0       0.013896  0.002076854  0.003394506  481.4976  403471.5  0.2615385   0.293232   0x00      0          0        0x43232544  INIT-ACK;COOKIE-ACK;SACK;DATA  6_0_0         0xc7        0x0000              17      17      4096      4096         4096         4096
A     1        0x0400000001004000  1108716598.694950  1108716598.763435  0.068485  1           3        eth:ipv4:sctp  00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800              192.168.170.8   07       "Private network"  7        192.168.170.56  07       "Private network"  7        132      5           5            2560         2560          512       512       512         0           0       0.022134  0.013697     0.005530534  73.00869  37380.45  0           0          0x00      10         0        0x00000eb0  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0
B     1        0x0400000001004001  1108716598.700597  1108716598.771526  0.070929  1           3        eth:ipv4:sctp  00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800              192.168.170.56  -        "-"                7        192.168.170.8   -        "-"                7        132      5           5            2560         2560          512       512       512         0           0       0.022732  0.0141858    0.005774313  70.49303  36092.43  0           0          0x00      10         0        0x43232544  DATA                           5_0_0         0x47        0x0000              0       0       0         4294967295   0            0

Same happens to the sctpChunkType_sid_flags_numDPkts_len_tsn_pid field in the packet file. And note the sctpCalCRCChkSum similar to the tcpFlags plugin.

head -n 10 ~/results/sctp-multi_packets.txt | tcol

%pktNo  flowInd  flowStat            time               pktIAT    pktTrip   flowDuration  numHdrs  hdrDesc        ethVlanID  srcMac             dstMac             ethType  srcIP           srcIPCC  srcIPOrg         srcPort  dstIP           dstIPCC  dstIPOrg         dstPort  l4Proto  pktLen  l7Len  sctpVTag    sctpChkSum  sctpCalCRCChkSum  sctpChunkType_sid_flags_numDPkts_len_tsn_pid  sctpErrType  sctpNChunks  sctpWin  sctpStat  l7Content
1       1        0x0400000001004000  1108716598.686079  0.000000  0.000000  0.000000      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      78      32     0x00000000  0x3761a746  0x3761a746        INIT_0_0x00_0_32_65535_1560164255_110011_     0x0000       1            65535    0x00
2       1        0x0400000001004001  1108716598.686375  0.000000  0.000296  0.000000      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      174     128    0x43232544  0xc9018524  0xc9018524        INIT-ACK_0_0x00_0_128_4096_13844_110011_      0x0000       1            4096     0x00
3       1        0x0400000001004000  1108716598.686862  0.000783  0.000487  0.000783      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      150     104    0x00000eb0  0xb85148ea  0xb85148ea        COOKIE-ECHO_0_0x00_0_104_0_0_0_               0x0000       1            0        0x00
4       1        0x0400000001004001  1108716598.687080  0.000705  0.000218  0.000705      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      50      4      0x43232544  0xceec2d79  0xceec2d79        COOKIE-ACK_0_0x00_0_4_0_0_0_                  0x0000       1            0        0x00
5       1        0x0400000001004000  1108716598.688291  0.001429  0.001211  0.002212      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   07       Private network  7        192.168.170.56  07       Private network  7        132      1102    512    0x00000eb0  0xcfbb0406  0xcfbb0406        DATA_0_0x07_1_528_0_1560164255_0_             0x0000       1            0        0x00      ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
5       1        0x0400000001004000  1108716598.688291  0.000000  0.000000  0.000000      3        eth:ipv4:sctp             00:e0:18:b1:0c:ad  00:60:08:45:e4:55  0x0800   192.168.170.8   -        -                7        192.168.170.56  -        -                7        132      1102    512    0x00000eb0  0xcfbb0406  0xcfbb0406        DATA_1_0x07_1_528_0_1560164256_0_             0x0000       1            0        0x00      ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
6       1        0x0400000001004001  1108716598.688538  0.001458  0.000247  0.002163      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      1118    1072   0x43232544  0xce0c78b4  0xce0c78b4        SACK_0_0x00_0_16_4096_1560164256_0_           0x0000       1            4096     0x00
6       1        0x0400000001004001  1108716598.688538  0.000000  0.000247  0.002163      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  07       Private network  7        192.168.170.8   07       Private network  7        132      1118    512    0x43232544  0xce0c78b4  0xce0c78b4        DATA_0_0x07_1_528_0_13844_0_                  0x0000       1            0        0x00      ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
6       1        0x0400000001004001  1108716598.688538  0.000000  0.000247  0.000000      3        eth:ipv4:sctp             00:60:08:45:e4:55  00:e0:18:b1:0c:ad  0x0800   192.168.170.56  -        -                7        192.168.170.8   -        -                7        132      1118    512    0x43232544  0xce0c78b4  0xce0c78b4        DATA_1_0x07_1_528_0_13845_0_                  0x0000       1            0        0x00      ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................

Conclusion

Don’t forget to reset all config for the next tutorials so that the output between your T2 and the tutorial webpage matches. Here is the reset command:

t2conf -a --reset && t2build -R

Have fun experimenting.