At Mon, 21 Mar 2016 19:21:59 +0530, Mukund Sivaraman <[email protected]> wrote:
> (1) Section 7.2.1. Authoritative Nameserver: > > > When deaggregating to correct the overlap, prefix lengths should be > > optimized to use the minimum necessary to cover the address space, in > > order to reduce the overhead that results from having multipe copies > > of the same answer. As a trivial example, if the Tailored Response > > for 1.2.0/20 is A but there is one exception of 1.2.3/24 for B, then > > the Authoritative Nameserver would need to provide Tailored Responses > > for 1.2.0/23, 1.2.2/24, 1.2.4/22, and 1.2.8/21 all pointing to A, and > > 1.2.3/24 to B. I'm confused about the revised Section 7.2.1 regarding overlapping prefixes. The 07 version of the draft now states: [...] Because it can't be guaranteed that queries for all longer prefix lengths would arrive before one that would be answered by the shorter prefix length, an Authoritative Nameserver MUST NOT overlap prefixes. But the above "trivial example" seems to talk about what an authoritative nameserver would do if it overlaps prefix...doesn't it simply break the MUST NOT in the first place? Also (ignoring the MUST NOT), what if a query is sent with a source prefix 1.2.1/24? The best matching prefix is 1.2.0/20, so isn't the tailored response A with the scope prefix length of 20? I mean, shouldn't the above deaggregated prefixes be incomplete? -- JINMEI, Tatuya _______________________________________________ DNSOP mailing list [email protected] https://www.ietf.org/mailman/listinfo/dnsop
