On Thu, Jul 26, 2018 at 09:33:20PM -0700, Spencer Dawkins wrote: > ---------------------------------------------------------------------- > COMMENT: > ---------------------------------------------------------------------- [snip] > > This next one is well within the "Spencer wouldn't have done it this way, but > Spencer's not the working group, or the IETF" range, but > > However, in the typical case a server will not know in advance > whether a client supports DSO, so in general, unless it is known in > advance by other means that a client does support DSO, a server MUST > NOT initiate DSO request messages or DSO unacknowledged messages > until a DSO Session has been mutually established by at least one > successful DSO request/response exchange initiated by the client, as > described below. Similarly, unless it is known in advance by other > means that a server does support DSO, a client MUST NOT initiate DSO > unacknowledged messages until after a DSO Session has been mutually > established. > > seems fragile, especially in environments where clients can come and go, and > servers may be addressed using anycast (so I knew in advance that the four > servers at that anycast address supported DSO, but somebody installed a fifth > server that does not). Is that unlikely to be a problem?
Note that the client is only prohibted from using "unacknowledged" (one-shot) messages -- it can send always normal requests and use the presence of a reply to determine server support, on this connection. So this seems like a pretty vanilla "client initiates" thing, if I understand correctly. -Benjamin [snip] _______________________________________________ DNSOP mailing list DNSOP@ietf.org https://www.ietf.org/mailman/listinfo/dnsop
