The Seattle SAGE Group
An Advanced Overview of IPv6
Path MTU and Fragmenting in IPv6
- IPv6 packets must not be fragmented enroute. All
fragmentation will be done at the source node, and defragmenting
occurs at the destination.
- The minimum packet size is 576 octets.
- IPv6 nodes should use path MTU discovery to determine the
MTU from the source to the destination, to take advantage of MTU's
> 576. However, a minimal implementation could restrict itself to
just 576.
- All nodes must be able to accept a packet that is as large
as 1500 octets after defragmentation, including the IPv6 header.
- Nodes should not send packets that reassemble to larger than 1500
octets after defragmentation, unless there is specific knowledge
that the destination can handle a larger size.
More info:
rfc1981