Subject: [SIP] maddr and NATs

From: Dvir Oren <[email-masked]>
Date: Mon, 24 Jul 2000 12:26:48 +0300 (IDT)

If a SIP entity adds an 'maddr' parameters, and that entity is
behind a NAT, the address of the maddr will not work.  I'm assuming
here that the SIP agent adds an IP address. There is also a problem 
when the client adds a Contact, and it is behind a NAT.

For Via fields - there is a received tag.  But for Contact, nobody will 
check that address.

It seems to me like there would be better chances passing a NAT if
there were no Contacts.

-- 
Dvir Oren               <[email-masked]>
Lucid VON Ltd.     <http://www.lucidvon.com>
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From: Jonathan Rosenberg <[email-masked]>
Date: Tue, 25 Jul 2000 03:23:09 -0400

The NAT issue is much more complex than this. See:
http://www.cs.columbia.edu/~jdrosen/papers/draft-rosenberg-sip-firewalls-00.txt

-Jonathan R.

-- 
Jonathan D. Rosenberg                       72 Eagle Rock Ave.
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