Subject: Re: DNS-SD in getaddrinfo()
To: Johan Danielsson <joda@pdc.kth.se>
From: Pelle Johansson <morth@morth.org>
List: tech-net
Date: 06/03/2004 14:52:28
2004-06-03 kl. 13.03 skrev Johan Danielsson:
> Each protocol has to have a defined mechanism for how to locate its
> service. You can't just stop or start using SRV on your own, so having
> this switch under user control is rather meaningless. I think that an
> AI_SRV flag is fine (and then it should only return SRV records). Next
> step is to amend rfc2553 with it.
Well, even with the AI_SRV flag, if a service record can not be found,
a normal lookup should be done. It's likely a service aware
administrator would add the *._tcp and *._udp records for unprovided
services.
I can certainly see the value of a user configurable option. The SRV
records are compatible with existing services and if a user wants to
use it with them, she should be able to. The RFC recommends against it,
but doesn't forbid it. Currently we are in a situation where we often
manually enter the service name in the host lookup (www.netbsd.org,
ftp.sunet.se, secure.bank.com etc). SRV records offer a simplification
over that, and to require specific application support when it isn't
needed seems unnecessary.
--
Pelle Johansson
<morth@morth.org>