> Dino, Hey Tom. I should make it clear that I am replying to email in the context of "user requirements", that means end user requirements. Hence my comment about 1400.
> Definitely at least for a limited domain. For instance, AFAIK Google > is using 9K MTUs in their internal networks. Whether the benefits of a I am well aware of this but this is server to server and isn't related to end-user requirements. And note, internal networks don't have an MTU problem because they can force 9K MTUs. > larger MTU scales to the whole Internet is probably still an open Right. > question, however QUIC seems to require at least an MTU of 1280 bytes I have tested QUIC over LISP and when interface MTUs are 1400, you can send 1280-byte packets over IPv4 (1280+8+8+20)=1316 and over IPv6 (1280+8+8+40)=1336 which keeps the packets <= 1400. So any protocol above IP could send more than 1280 (120 bytes more to reach 1400-byte MTUs) with plenty of room for tunnels (even nested tunnels to 2 levels). > so there are some attempts to enforce a baseline MTU for the Internet > greater than the specified minimums (at least greater than 64 bytes or > 576 bytes for IPv4 MTU minimums. Yes, and I vote for 1400. Just because I have tested it in many cases over many years on a LISP overlay. In cases for data center MTU, I would suggest 8900 (9000-100) and be consistent saying we save 100 bytes of packet head-room for overlays. > Tom Thanks, Dino _______________________________________________ Int-area mailing list Int-area@ietf.org https://www.ietf.org/mailman/listinfo/int-area
