Re: Seperating URC format and URN->URC resolution

Alexander Dupuy (dupuy@smarts.com)
Fri, 29 Apr 1994 23:51:05 +0500

Date: Fri, 29 Apr 1994 23:51:05 +0500
From: dupuy@smarts.com (Alexander Dupuy)
Message-Id: <9404300351.AA10879@brainy.smarts.com>
To: peterd@bunyip.com, mitra@pandora.sf.ca.us
Subject: Re: Seperating URC format and URN->URC resolution

> Starting from a "urn:fred:12345"
> Ask DNS for TXT record for "fred.uri.int"
> if success
> then
> interpret text record to decide server
> case "whois"
> contact whois server
> case "http"
> contact http server
> case "prospero"
> contact prospero server
> else
> ask DNS with "gethostbyname" for fred.uri.int
> contact "fred.uri.int" on default port with default protocol.
> endif
>
>
> I have two problems with this - but both could be worked around if this
> is really what is wanted.
>
> a) it takes at least one more connection to DNS for the default case,
> which is an unneccessary extra delay.

Actually, you can ask DNS for all records for fred.uri.int at the same time,
so you don't need to go to DNS twice.

> b) a client writer has to implement *ALL* the protocols above, in order
> to know that they can resolve any URN they are presented with.

You never know that you can resolve any URN; but we should require that all
URN servers support the "default" protocol, whenever we decide what that is.
In the meantime, people can resolve things using any protocols they support
from the TXT records. Eventually, all clients will add support for the
default protocol. I think this addresses your concern.

@alex