In message <[email protected]>, "Fred Baker (fred)" writes: > I suppose I'm the contrarian, but this draft gives me some heartburn > surrounding the robustness principle. Yes, > TCP MSS generally limits the use of fragmentation for IPv6. We don't have a > counterpart to MSS for UDP, and othe > rs have noted that OSPF etc may have issues. > > Thinking hypothetically, it would be unusual for OSPF to not be able to > manage packet size via LSA choice, but s > uppose I am on an interface that has a given MTU, and I have a single LSA > that is larger than that MTU, perhaps > a Router LSA on a wide fan-out unit. Deprecating the fragmentation capability > forces each client of the network > layer to create a means for fragmentation/segmentation. That might be some > other protocol that essentially dupli > cates what we're deprecating, or it could be something in which a router has > to make enough routing instances of > itself to split the Router LSA across them, or something like that. > > Personally, I think I would prefer a statement that says that the first > fragment MUST contain the transport head > er (which Fernando has been pushing), and encourages transports and > applications to implement some variation on > PMTU rather than depending on fragmentation, but not deprecating the > capability.
Or additionallty supply the information the firewall is looking for in a skipable hop-by-hop option. For UDP that would be the two ports. 6 to 8 extra octets per fragment. > -------------------------------------------------------------------- > IETF IPv6 working group mailing list > [email protected] > Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 > -------------------------------------------------------------------- -- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: [email protected] -------------------------------------------------------------------- IETF IPv6 working group mailing list [email protected] Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
