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each / draft-aname

work on a draft to standardize ANAME/ALIAS records to allow CNAME-like records at the zone apex
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Considerations related to ANAME behavior #68

Closed matje closed 5 years ago

matje commented 5 years ago

Brian Dickson:

I have elaborated on this problem previously, but will do so again for completeness/context:

  • There can be differences (possibly significant differences) in the results returned for resolution of the "target" between the ANAME authoritative server, and the querying resolver. o E.g. Any sort of "stupid DNS tricks" that return different values based on either physical topology (anycast instance) or geo-ip (client-subnet)> o That discrepancy can direct clients to a suboptimal server, where suboptimal can even be, from a user perspective, badly broken (e.g. wrong language, illegal content, etc.)> * The interactions on TTLs and the need for repeated lookups can have adverse impacts on both clients, resolvers, and auth servers o An auth server might want to use longer TTLs to reduce query volume, for ANAME values that do not change frequently (A/AAAA TTL set to same as ANAME TTL) o The original A/AAAA TTL (for the "target" owner name's A/AAAA RRDATA) might be short because it changes frequently (e.g. CDNs)