March 27, 2017
6:06 p.m.
I propose RSSAC caucus explore an understanding of the MTU, MSS and fragmentation behaviour of all instances of the roots, in IPv6 and IPv4.
Just for your information, bind-9.11.0 (I don't know when, but at least from -P1) set 1220 to MAX TCP Segment size, regardless of the IP version being used (see at around line 3701 of lib/isc/unix/socket.c). This may reduce the efficiency of TCP transaction a little bit, but will cause no harm. We may need some more discussion to define a correct way in general (not limited to DNS case) how we can handle TCP segment size. We may able to control it with IPV6_USE_MIN_MTU and TCP_MAXSEG, however, each application must set appropriately. But this may not a business of RSSAC caucus. -- Akira Kato