The acknowledgement numbers in the three-way-handshake used by TCP

The TCP header, shown in the TCP chapter of Computer Networking: Principles, Protocols and Practice contains a sequence number and an acknowledgement number. The three segments below correspond to the three-way handshake that is used to establish a TCP connection.


Acknowledgement numbers

Can you infer the acknowledgement numbers of the second and third TCP segments exchanged in the three-way-handshake below ?

# Length Resumé Status
0 24 bytes <TCP: SYN, SEQ: 4207062859, ACK: 0, MSS>
1 24 bytes <TCP: ACK, SYN, SEQ: 4037529898, ACK: ??, MSS>  
2 20 bytes <TCP: ACK, SEQ: 4207062860, ACK: ??>  

0000  d1d004d2fac2af4b  0000000060027080  
0010  4f900000020405a0                    

0000  ÑÐ.Òú¯K....`.p.
0010  O.......        
  • TCP:
    • Source Port: 53712
    • Destination Port: 1234
    • Sequence Number: 4207062859
    • Acknowledgment Number: 0
    • Data Offset: 6
    • Reserved: 0
    • NS: 0
    • CWR: 0
    • ECE: 0
    • URG: 0
    • ACK: 0
    • PSH: 0
    • RST: 0
    • SYN: 1
    • FIN: 0
    • Window: 28800
    • Checksum: 20368
    • Urgent Pointer: 0
    • Options: Maximum Segment Size
      • Kind: 2
      • Length: 4
      • Max Seg Size: 1440
0000  04d2d1d0f0a7d12a  ????????60127080  
0010  4f900000020405a0                    

0000  .ÒÑÐð§Ñ*????`.p.
0010  O.......        
  • TCP:
    • Source Port: 1234
    • Destination Port: 53712
    • Sequence Number: 4037529898
    • Acknowledgment Number:
    • Data Offset: 6
    • Reserved: 0
    • NS: 0
    • CWR: 0
    • ECE: 0
    • URG: 0
    • ACK: 1
    • PSH: 0
    • RST: 0
    • SYN: 1
    • FIN: 0
    • Window: 28800
    • Checksum: 20368
    • Urgent Pointer: 0
    • Options: Maximum Segment Size
      • Kind: 2
      • Length: 4
      • Max Seg Size: 1440
0000  d1d004d2fac2af4c  ????????50107080  
0010  4f8c0000                            

0000  ÑÐ.Òú¯L????P.p.
0010  O...            
  • TCP:
    • Source Port: 53712
    • Destination Port: 1234
    • Sequence Number: 4207062860
    • Acknowledgment Number:
    • Data Offset: 5
    • Reserved: 0
    • NS: 0
    • CWR: 0
    • ECE: 0
    • URG: 0
    • ACK: 1
    • PSH: 0
    • RST: 0
    • SYN: 0
    • FIN: 0
    • Window: 28800
    • Checksum: 20364
    • Urgent Pointer: 0

Information

Author(s) Olivier Bonaventure
Deadline No deadline
Submission limit No limitation
Category Tags TCP

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