Information

Author(s) Olivier Bonaventure
Deadline No deadline
Submission limit No limitation
Category tags IPv6

Tags

Sign in

IPv6 : the next header -- UDP version

The IPv6 header, shown in the IPv6 chapter of Computer Networking: Principles, Protocols and Practice contains a Next Header field that usually indicates the protocol used for the packet payload.


Next Header for a packet carrying a UDP segment

Can you infer the Next Header field of this packet knowing that it contains a UDP segment.

# Length Summary Status
0 48 bytes User Datagram Protocol, Src Port: 50119, Dst Port: 53  

0000  600f35d30028??ff  200106a8308f0002  
0010  48e995ae3a92922d  200106a830810001  
0020  0000000000000053  c3c7003500285a49  

0000  `.5Ó.(?ÿ ..¨0...
0010  Hé.®:..- ..¨0...
0020  .......SÃÇ.5.(ZI
  • Internet Protocol Version 6, Src: 2001:6a8:308f:2:48e9:95ae:3a92:922d, Dst: 2001:6a8:3081:1::53
    • 0110 .... = Version: 6
      • .... 0000 0000 .... .... .... .... .... = Traffic Class: 0x00 (DSCP: CS0, ECN: Not-ECT)
        • .... 0000 00.. .... .... .... .... .... = Differentiated Services Codepoint: Default (0)
          • .... .... ..00 .... .... .... .... .... = Explicit Congestion Notification: Not ECN-Capable Transport (0)
          • .... .... .... 1111 0011 0101 1101 0011 = Flow Label: 0xf35d3
            • Payload Length: 40
              • Next Header: UDP (?)
              • Hop Limit: 255
                • Source: 2001:6a8:308f:2:48e9:95ae:3a92:922d
                  • Destination: 2001:6a8:3081:1::53
                  • User Datagram Protocol, Src Port: 50119, Dst Port: 53
                    • Source Port: 50119
                      • Destination Port: 53
                        • Length: 40
                          • Checksum: 0x5a49 [unverified]