Subject: Why are location servers and redirect servers defined as two separate servers.

From: [email-masked]
Date: Tue, 29 Feb 2000 14:30:18 -0600

Hi,

In the RFC 2543, the location server and redirect server are defined as two
different servers which could optionally be co-located.
My understanding is
     a redirect server gets an INVITE request and sends a 3XX response (or a
failure response ) for the request.
     a location server gets a location request and sends a location response.
Aren't the two the same. So why define a location server in the SIP world and
leave the interface undefined instead it would be better if we collapsed them
into one.
To me the location server seems more like a database behind a redirect server.
Could somebody please clarify this.

Thanks,

Anoop Tripathi

3COM

---

From: Jonathan Rosenberg <[email-masked]>
Date: Thu, 02 Mar 2000 02:04:21 -0500

>      a location server gets a location request and sends a location response.

One is a SIP entity. The other is the back end database/logic to that
SIP entity. Like stateless proxy and registrar, location server is a
LOGICAL entity, which may or may not exist as a separate component or
even be a component at all. A redirect server may have an in memory
database of locations for a user, in which case this memory database is
the location server. A proxy may use finger to find a user, in which
case finger is the location server. A proxy might have an LDAP interface
to a corporate wp database, in which case that database is the location
server. We can't "collapse" the location server into the redirect or
proxy server, because *logically* they are very different entities. In
physical realization, of course they can be collapsed if thats what you
want.

-Jonathan R.
-- 
Jonathan D. Rosenberg                       200 Executive Drive
Chief Scientist                             Suite 120 
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