Another TCP connection release

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Connection release

In this trace, the local host issued close immediately after having accepted the connection. Can you fill the missing information in the last four TCP segments ?

#	Length	Summary
0	24 bytes	`Transmission Control Protocol, Src Port: 43508, Dst Port: 8080, Seq: 2520729040, Len: 0`
1	24 bytes	`Transmission Control Protocol, Src Port: 8080, Dst Port: 43508, Seq: 0, Ack: 2520729041, Len: 0`
2	20 bytes	`Transmission Control Protocol, Src Port: 43508, Dst Port: 8080, Seq: 2520729041, Ack: 1, Len: 0`
3	20 bytes	`Transmission Control Protocol, Src Port: 43508, Dst Port: 8080, Seq: ????, Ack: ????, Len: 0`
4	20 bytes	`Transmission Control Protocol, Src Port: 8080, Dst Port: 43508, Seq: ????, Ack: ????, Len: 0`
5	20 bytes	`Transmission Control Protocol, Src Port: 43508, Dst Port: 8080, Seq: ????, Ack: ????, Len: 0`

0000 a9f41f90963f45d0 0000000060024e20
0010 021c0000020403e8

0000 ©ô...?EÐ....`.N
0010 .......è

Transmission Control Protocol, Src Port: 43508, Dst Port: 8080, Seq: 2520729040, Len: 0
- Source Port: 43508
- Destination Port: 8080
- TCP Segment Len: 0
- Sequence number: 2520729040
- Acknowledgment number: 0
- 0110 .... = Header Length: 24 bytes (6)
- 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
  - .... ...0 .... = Acknowledgment: Not set
  - .... .... 0... = Push: Not set
  - .... .... .0.. = Reset: Not set
  - .... .... ..1. = Syn: Set
  - .... .... ...0 = Fin: Not set
- Window size value: 20000
- Calculated window size: 20000
- Checksum: 0x021c [unverified]
- Urgent pointer: 0
- Options: (4 bytes), Maximum segment size
  - TCP Option - Maximum segment size: 1000 bytes
    - Kind: Maximum Segment Size (2)
    - Length: 4
    - MSS Value: 1000

0000 1f90a9f400000000 963f45d160122710
0010 cb3f0000020403e8

0000 ..©ô.....?EÑ`.'.
0010 Ë?.....è

Transmission Control Protocol, Src Port: 8080, Dst Port: 43508, Seq: 0, Ack: 2520729041, Len: 0
- Source Port: 8080
- Destination Port: 43508
- TCP Segment Len: 0
- Sequence number: 0
- Acknowledgment number: 2520729041
- 0110 .... = Header Length: 24 bytes (6)
- 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
  - .... .... ..1. = Syn: Set
  - .... .... ...0 = Fin: Not set
- Window size value: 10000
- Calculated window size: 10000
- Checksum: 0xcb3f [unverified]
- Urgent pointer: 0
- Options: (4 bytes), Maximum segment size
  - TCP Option - Maximum segment size: 1000 bytes
    - Kind: Maximum Segment Size (2)
    - Length: 4
    - MSS Value: 1000

0000 a9f41f90963f45d1 0000000150104e20
0010 02180000

0000 ©ô...?EÑ....P.N
0010 ....

Transmission Control Protocol, Src Port: 43508, Dst Port: 8080, Seq: 2520729041, Ack: 1, Len: 0
- Source Port: 43508
- Destination Port: 8080
- TCP Segment Len: 0
- Sequence number: 2520729041
- Acknowledgment number: 1
- 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: 20000
- Calculated window size: 20000
- Window size scaling factor: -2 (no window scaling used)
- Checksum: 0x0218 [unverified]
- Urgent pointer: 0

0000 a9f41f90???????? ????????50114e20
0010 02180000

Transmission Control Protocol, Src Port: 43508, Dst Port: 8080, Seq: ????, Ack: ????, Len: 0
- Source Port: 43508
- Destination Port: 8080
- TCP Segment Len: 0
- Sequence number: ?
- Acknowledgment number: ?
- 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
  - .... .... ...1 = Fin: Set
- Window size value: 20000
- Calculated window size: 20000
- Window size scaling factor: -2 (no window scaling used)
- Checksum: 0x0218 [unverified]
- Urgent pointer: 0

0000 1f90a9f4???????? ????????50112710
0010 e12e0000

Transmission Control Protocol, Src Port: 8080, Dst Port: 43508, Seq: ????, Ack: ????, Len: 0
- Source Port: 8080
- Destination Port: 43508
- TCP Segment Len: 0
- Sequence number: ?
- Acknowledgment number: ?
- 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
  - .... .... ...1 = Fin: Set
- Window size value: 10000
- Calculated window size: 10000
- Window size scaling factor: -2 (no window scaling used)
- Checksum: 0xe12e [unverified]
- Urgent pointer: 0

0000 a9f41f90???????? ????????50104e20
0010 02180000

Transmission Control Protocol, Src Port: 43508, Dst Port: 8080, Seq: ????, Ack: ????, Len: 0
- Source Port: 43508
- Destination Port: 8080
- TCP Segment Len: 0
- Sequence number: ?
- Acknowledgment number: ?
- 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: 20000
- Calculated window size: 20000
- Window size scaling factor: -2 (no window scaling used)
- Checksum: 0x0218 [unverified]
- Urgent pointer: 0

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

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