Subject: RE: [SIP] Issue with domain names in Via header

From: Igor Slepchin <[email-masked]>
Date: Sat, 17 Mar 2001 15:58:55 -0500

> -----Original Message-----
> From: Gonzalo Camarillo [mailto:[email-masked]]
> 
> However, stateless proxies will not catch ICMP messages, 

Why not? Stateless proxies can still use connected UDP sockets; if a
connected socket to the upstream host already existed (and had been used)
before the response is forwarded, the ICMP error will be detected when the
response is first transmitted; otherwise, ICMP error will be detected when
the retransmission of the response is forwarded.

Besides, there is a separate issue with requiring n SRV records per cluster;
I believe this to be rather inconvenient.

---
Igor Slepchin

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---

From: Gonzalo Camarillo <[email-masked]>
Date: Sat, 17 Mar 2001 23:16:54 +0200

Igor,

> the retransmission of the response is forwarded.

Well, following this reasoning a stateless proxy might also use TCP. It
opens the connection, and send whatever message. Then, if it receives
more stuff, it will send it over that connection...

The idea behind a stateless proxy is that it scales pretty well since it
can handle a lot of connections in a very fast manner: it receives a
message, it forwards it, and it gorgets about it.

If any time a new request or response comes, the stateless server has to
check all the connected UDP sockets that is has to see it there is a
match, I think you would be better off implementing a stateful proxy.
Besides, you would also have to implement timeouts to close the sockets.
OK, this might not be SIP-related state information, but it is state
information anyway.
 
> I believe this to be rather inconvenient.

Could you elaborate on this (or send me a pointer)? 

Thanks,

Gonzalo

-- 
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