On Tue, Sep 11, 2012 at 02:45:12PM +0100, Brian E Carpenter wrote: > Thanks. Then it seems to me that a recommendation about the desirable > behaviour > of getnameinfo() and getaddrinfo() needs to be made, consistent with the final > recommendation for mDNS vs DNS. At least we should describe a consistent > deployment scenario.
But you can't _make_ such a recommendation, because different scenarios -- network-topologically indistinguishable from one another -- require very different conclusions. This is exactly the same problem MIF faced with the DNS server selection logic. You naturally want to use the DNS server that you believe is going to provide you with the right answers. But when you move networks (say, into the coffeeshop which is using Stupid DNS Tricks to authenticate you as a customer first), you actually need the _least good_ answer sometimes, in order to move you from your expensive mobile radio onto your cheap wifi. The same problem crops up here. Inside your house, mDNS is perhaps the right answer. But for bookmarking on your laptop that you carry on the road but want to use with your home network then, it's exactly the wrong answer. So this once again comes down to use cases, and trading userland functionality against complications that make the specification complex, and implementations tricky and therefore buggy. To moan just a little bit, this is why many of us think that the mutliple namespace approaches (seen in mDNS, llmnr, before those NetBIOS, and so on) are harmful. Inevitably, these systems get hooked up to the wider Internet, and the inconsistencies thereby revealed make people confused. (This isn't to say there is an obvious better answer, given the facts of the world about DNS name registration and resolution.) Best, A -- Andrew Sullivan [email protected] _______________________________________________ homenet mailing list [email protected] https://www.ietf.org/mailman/listinfo/homenet
