Reordering the segments exchanged on a connection

TCP, as explained in the TCP chapter of Computer Networking: Principles, Protocols and Practice includes a sequence number in each segment that carries data.

Paste this command into your terminal:

The password to connect is

Reorder the segments

During this connection, the client sent some data that was acknowledged by the server. Can you reorder the segments based on their sequence numbers and acknowledgements ? The trace starts at the third ack of the three-way handshake sent by the client to the server.

#	Length	Summary
0	20 bytes	`Transmission Control Protocol, Src Port: 1234, Dst Port: 53708, Seq: 3164923749, Ack: 2250678594, Len: 0`
1	22 bytes	`Transmission Control Protocol, Src Port: 53708, Dst Port: 1234, Seq: 2250678592, Ack: 3164923749, Len: 2`
2	20 bytes	`Transmission Control Protocol, Src Port: 1234, Dst Port: 53708, Seq: 3164923749, Ack: 2250678592, Len: 0`
3	20 bytes	`Transmission Control Protocol, Src Port: 53708, Dst Port: 1234, Seq: 2250678588, Ack: 3164923749, Len: 0`
4	22 bytes	`Transmission Control Protocol, Src Port: 53708, Dst Port: 1234, Seq: 2250678590, Ack: 3164923749, Len: 2`
5	20 bytes	`Transmission Control Protocol, Src Port: 1234, Dst Port: 53708, Seq: 3164923749, Ack: 2250678590, Len: 0`
6	20 bytes	`Transmission Control Protocol, Src Port: 1234, Dst Port: 53708, Seq: 3164923749, Ack: 2250678596, Len: 0`
7	22 bytes	`Transmission Control Protocol, Src Port: 53708, Dst Port: 1234, Seq: 2250678594, Ack: 3164923749, Len: 2`
8	22 bytes	`Transmission Control Protocol, Src Port: 53708, Dst Port: 1234, Seq: 2250678588, Ack: 3164923749, Len: 2`

0000 04d2d1ccbca4e765 8626a14250107080
0010 00000000

0000 .ÒÑÌ¼¤çe.&¡BP.p.
0010 ....

Transmission Control Protocol, Src Port: 1234, Dst Port: 53708, Seq: 3164923749, Ack: 2250678594, Len: 0
- Source Port: 1234
- Destination Port: 53708
- Sequence number: 3164923749
- Acknowledgment number: 2250678594
- 0101 .... = Header Length: 20 bytes (5)
- Flags
  - 000. .... .... = Reserved: Not set
  - ...0 .... .... = Nonce: Not set
  - .... 0... .... = Congestion Window Reduced (CWR): Not set
  - .... .0.. .... = ECN-Echo: Not set
  - .... ..0. .... = Urgent: Not set
  - .... ...1 .... = Acknowledgment: Set
  - .... .... 0... = Push: Not set
  - .... .... .0.. = Reset: Not set
  - .... .... ..0. = Syn: Not set
  - .... .... ...0 = Fin: Not set
- Window size value: 28800
- Urgent pointer: 0

0000 d1cc04d28626a140 bca4e76550187080
0010 00000000330a

0000 ÑÌ.Ò.&¡@¼¤çeP.p.
0010 ....3.

Transmission Control Protocol, Src Port: 53708, Dst Port: 1234, Seq: 2250678592, Ack: 3164923749, Len: 2
- Source Port: 53708
- Destination Port: 1234
- Sequence number: 2250678592
- Acknowledgment number: 3164923749
- 0101 .... = Header Length: 20 bytes (5)
- Flags
  - 000. .... .... = Reserved: Not set
  - ...0 .... .... = Nonce: Not set
  - .... 0... .... = Congestion Window Reduced (CWR): Not set
  - .... .0.. .... = ECN-Echo: Not set
  - .... ..0. .... = Urgent: Not set
  - .... ...1 .... = Acknowledgment: Set
  - .... .... 1... = Push: Set
  - .... .... .0.. = Reset: Not set
  - .... .... ..0. = Syn: Not set
  - .... .... ...0 = Fin: Not set
- Window size value: 28800
- Urgent pointer: 0
- TCP payload (2 bytes)

0000 04d2d1ccbca4e765 8626a14050107080
0010 00000000

0000 .ÒÑÌ¼¤çe.&¡@P.p.
0010 ....

Transmission Control Protocol, Src Port: 1234, Dst Port: 53708, Seq: 3164923749, Ack: 2250678592, Len: 0
- Source Port: 1234
- Destination Port: 53708
- Sequence number: 3164923749
- Acknowledgment number: 2250678592
- 0101 .... = Header Length: 20 bytes (5)
- Flags
  - 000. .... .... = Reserved: Not set
  - ...0 .... .... = Nonce: Not set
  - .... 0... .... = Congestion Window Reduced (CWR): Not set
  - .... .0.. .... = ECN-Echo: Not set
  - .... ..0. .... = Urgent: Not set
  - .... ...1 .... = Acknowledgment: Set
  - .... .... 0... = Push: Not set
  - .... .... .0.. = Reset: Not set
  - .... .... ..0. = Syn: Not set
  - .... .... ...0 = Fin: Not set
- Window size value: 28800
- Urgent pointer: 0

0000 d1cc04d28626a13c bca4e76550107080
0010 00000000

0000 ÑÌ.Ò.&¡<¼¤çeP.p.
0010 ....

Transmission Control Protocol, Src Port: 53708, Dst Port: 1234, Seq: 2250678588, Ack: 3164923749, Len: 0
- Source Port: 53708
- Destination Port: 1234
- Sequence number: 2250678588
- Acknowledgment number: 3164923749
- 0101 .... = Header Length: 20 bytes (5)
- Flags
  - 000. .... .... = Reserved: Not set
  - ...0 .... .... = Nonce: Not set
  - .... 0... .... = Congestion Window Reduced (CWR): Not set
  - .... .0.. .... = ECN-Echo: Not set
  - .... ..0. .... = Urgent: Not set
  - .... ...1 .... = Acknowledgment: Set
  - .... .... 0... = Push: Not set
  - .... .... .0.. = Reset: Not set
  - .... .... ..0. = Syn: Not set
  - .... .... ...0 = Fin: Not set
- Window size value: 28800
- Urgent pointer: 0

0000 d1cc04d28626a13e bca4e76550187080
0010 00000000320a

0000 ÑÌ.Ò.&¡>¼¤çeP.p.
0010 ....2.

Transmission Control Protocol, Src Port: 53708, Dst Port: 1234, Seq: 2250678590, Ack: 3164923749, Len: 2
- Source Port: 53708
- Destination Port: 1234
- Sequence number: 2250678590
- Acknowledgment number: 3164923749
- 0101 .... = Header Length: 20 bytes (5)
- Flags
  - 000. .... .... = Reserved: Not set
  - ...0 .... .... = Nonce: Not set
  - .... 0... .... = Congestion Window Reduced (CWR): Not set
  - .... .0.. .... = ECN-Echo: Not set
  - .... ..0. .... = Urgent: Not set
  - .... ...1 .... = Acknowledgment: Set
  - .... .... 1... = Push: Set
  - .... .... .0.. = Reset: Not set
  - .... .... ..0. = Syn: Not set
  - .... .... ...0 = Fin: Not set
- Window size value: 28800
- Urgent pointer: 0
- TCP payload (2 bytes)

0000 04d2d1ccbca4e765 8626a13e50107080
0010 00000000

0000 .ÒÑÌ¼¤çe.&¡>P.p.
0010 ....

Transmission Control Protocol, Src Port: 1234, Dst Port: 53708, Seq: 3164923749, Ack: 2250678590, Len: 0
- Source Port: 1234
- Destination Port: 53708
- Sequence number: 3164923749
- Acknowledgment number: 2250678590
- 0101 .... = Header Length: 20 bytes (5)
- Flags
  - 000. .... .... = Reserved: Not set
  - ...0 .... .... = Nonce: Not set
  - .... 0... .... = Congestion Window Reduced (CWR): Not set
  - .... .0.. .... = ECN-Echo: Not set
  - .... ..0. .... = Urgent: Not set
  - .... ...1 .... = Acknowledgment: Set
  - .... .... 0... = Push: Not set
  - .... .... .0.. = Reset: Not set
  - .... .... ..0. = Syn: Not set
  - .... .... ...0 = Fin: Not set
- Window size value: 28800
- Urgent pointer: 0

0000 04d2d1ccbca4e765 8626a14450107080
0010 00000000

0000 .ÒÑÌ¼¤çe.&¡DP.p.
0010 ....

Transmission Control Protocol, Src Port: 1234, Dst Port: 53708, Seq: 3164923749, Ack: 2250678596, Len: 0
- Source Port: 1234
- Destination Port: 53708
- Sequence number: 3164923749
- Acknowledgment number: 2250678596
- 0101 .... = Header Length: 20 bytes (5)
- Flags
  - 000. .... .... = Reserved: Not set
  - ...0 .... .... = Nonce: Not set
  - .... 0... .... = Congestion Window Reduced (CWR): Not set
  - .... .0.. .... = ECN-Echo: Not set
  - .... ..0. .... = Urgent: Not set
  - .... ...1 .... = Acknowledgment: Set
  - .... .... 0... = Push: Not set
  - .... .... .0.. = Reset: Not set
  - .... .... ..0. = Syn: Not set
  - .... .... ...0 = Fin: Not set
- Window size value: 28800
- Urgent pointer: 0

0000 d1cc04d28626a142 bca4e76550187080
0010 00000000340a

0000 ÑÌ.Ò.&¡B¼¤çeP.p.
0010 ....4.

Transmission Control Protocol, Src Port: 53708, Dst Port: 1234, Seq: 2250678594, Ack: 3164923749, Len: 2
- Source Port: 53708
- Destination Port: 1234
- Sequence number: 2250678594
- Acknowledgment number: 3164923749
- 0101 .... = Header Length: 20 bytes (5)
- Flags
  - 000. .... .... = Reserved: Not set
  - ...0 .... .... = Nonce: Not set
  - .... 0... .... = Congestion Window Reduced (CWR): Not set
  - .... .0.. .... = ECN-Echo: Not set
  - .... ..0. .... = Urgent: Not set
  - .... ...1 .... = Acknowledgment: Set
  - .... .... 1... = Push: Set
  - .... .... .0.. = Reset: Not set
  - .... .... ..0. = Syn: Not set
  - .... .... ...0 = Fin: Not set
- Window size value: 28800
- Urgent pointer: 0
- TCP payload (2 bytes)

0000 d1cc04d28626a13c bca4e76550187080
0010 00000000310a

0000 ÑÌ.Ò.&¡<¼¤çeP.p.
0010 ....1.

Transmission Control Protocol, Src Port: 53708, Dst Port: 1234, Seq: 2250678588, Ack: 3164923749, Len: 2
- Source Port: 53708
- Destination Port: 1234
- Sequence number: 2250678588
- Acknowledgment number: 3164923749
- 0101 .... = Header Length: 20 bytes (5)
- Flags
  - 000. .... .... = Reserved: Not set
  - ...0 .... .... = Nonce: Not set
  - .... 0... .... = Congestion Window Reduced (CWR): Not set
  - .... .0.. .... = ECN-Echo: Not set
  - .... ..0. .... = Urgent: Not set
  - .... ...1 .... = Acknowledgment: Set
  - .... .... 1... = Push: Set
  - .... .... .0.. = Reset: Not set
  - .... .... ..0. = Syn: Not set
  - .... .... ...0 = Fin: Not set
- Window size value: 28800
- Urgent pointer: 0
- TCP payload (2 bytes)

Author(s)	Olivier Bonaventure
Deadline	No deadline
Submission limit	No limitation
Category tags	tcp

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