IPv6 : packet fragmentation

IPv6, described in the IPv6 chapter of Computer Networking: Principles, Protocols and Practice includes a packet fragmentation mechanism that allows to send large packets as a series of fragments.


Reorder the fragments

Can you reorder the packet packet fragments that were captured while a host was using ping6 to verify the reachability of destination 2001:7ab:2::b with packets that are longer than the MTU ? This packet was sent by a Linux host that sends the first fragment of the packet last.

# Length Resumé Status
0 48 bytes <Fragment Header: >
1 48 bytes <Fragment Header: >

0000  6000df0404d82c3e  200107ab00010000  
0010  000000000000000a  200107ab00020000  
0020  000000000000000b  3a00000154d73dbe  

0000  `.ß..Ø,> ..«....
0010  ........ ..«....
0020  ........:...T×=¾
  • IPv6:
    • Version: 6
    • Traffic Class UB: 0
    • Traffic Class LB: 0
    • Flow Label UB: 0
    • Flow Label LB: 57092
    • Payload Length: 1240
    • Next Header: 44
    • Hop Limit: 62
    • Source Address: 2001:7ab:1::a
    • Destination Address: 2001:7ab:2::b
    • Payload: Fragment Header
      • Next Header: 58
      • Reserved: 0
      • Fragment Offset LB: 0
      • Fragment Offset UB: 0
      • Res: 0
      • M flag: 1
      • Identification: 1423392190
0000  6000df0402382c3e  200107ab00010000  
0010  000000000000000a  200107ab00020000  
0020  000000000000000b  3a0005a854d73d00  

0000  `.ß..8,> ..«....
0010  ........ ..«....
0020  ........:..¨T×=.
  • IPv6:
    • Version: 6
    • Traffic Class UB: 0
    • Traffic Class LB: 0
    • Flow Label UB: 0
    • Flow Label LB: 57092
    • Payload Length: 568
    • Next Header: 44
    • Hop Limit: 62
    • Source Address: 2001:7ab:1::a
    • Destination Address: 2001:7ab:2::b
    • Payload: Fragment Header
      • Next Header: 58
      • Reserved: 0
      • Fragment Offset LB: 5
      • Fragment Offset UB: 21
      • Res: 0
      • M flag: 0
      • Identification: 1423392000

Information

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

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