Subject: RE: [Sip] Symmetric NAT issue

From: "Christian Stredicke" <[email-masked]>
Date: Tue, 21 Sep 2004 14:34:39 +0200

IMVHO SBC that use ICE are a smart alternative to using TURN. UA that
are not aware of ICE, STUN, TURN or NAT will run media through the B2BUA
while ICE-aware devices can bypass them. IMEHO ist much easier to
implement STUN/ICE than TURN (well, we did/tried it) and it solves the
problem with the "dumb" devices. Paired with DNS SRV and STUN its
possible to automatically detect the nearest SBC, in case the SBC is
necessary to relay media for symmetrical NAT.

CS

-----Original Message-----
From: [email-masked] [mailto:[email-masked]] On Behalf Of
Jonathan Rosenberg
Sent: Tuesday, September 21, 2004 9:16 AM
To: vikram
Cc: [email-masked]
Subject: Re: [Sip] Symmetric NAT issue

There are some TURN implementations. There are security and interop
benefits of TURN over the b2bua-wm approach used by current SBC
products. TURN will work with e2e sip security mechanisms, and does not
require a b2bua function in the network, which can cause problems with
new sip features (see, for example, the recent thread on how sbc's
interfere with gruu operation).

Thanks,
Jonathan R.

vikram wrote:

> Hello All,
>                    We are facing lots of problem with NAT traversal 
> for SIP .
>      It is not working behind symmetric NAT. I could see various 
> solutions but none is 100% promising. ??
>       e.g   1) ALGs(intelligent firewall)                2)Session 
> Border Controller
>               3)TURN
>               4) Tunneling (e.g X-tunnel)
>               5)  RTP proxy ??
>       Which one is best ???
> 
>       we are looking for a solution which could work by just *changing

> our client* and/or *by using a global server*...
>      ALGs require upgradation of Firewalls, which everybody cant
afford. 
> Tunneling too require some server entity within Intranet and
>       a global server, which again is not possible to deploy at every 
> place  .
> 
>      Now question remains about TURN and SBCs. TURN is still in 
> process ..has anybody implemented. ?
>      Session border controller seems promising ...?
>      but could i have a SBC for a trial period with whom i can connect

> my client    ??
>      *Dose anybody provide free SBC service as of  SIP proxies ??*
>      
>     Please Help !!!!
> 
> 
>    regards
> 
>   Vikram
>                        
> 
> 
> 
> 
> _______________________________________________
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> 

-- 
Jonathan D. Rosenberg, Ph.D.                600 Lanidex Plaza
Chief Technology Officer                    Parsippany, NJ 07054-2711
dynamicsoft
[email-masked]                     FAX:   (973) 952-5050
http://www.jdrosen.net                      PHONE: (973) 952-5000
http://www.dynamicsoft.com

_______________________________________________
Sip mailing list  https://www1.ietf.org/mailman/listinfo/sip
This list is for NEW development of the core SIP Protocol Use
[email-masked] for questions on current sip Use
[email-masked] for new developments on the application of sip

_______________________________________________
Sip mailing list  https://www1.ietf.org/mailman/listinfo/sip
This list is for NEW development of the core SIP Protocol
Use [email-masked] for questions on current sip
Use [email-masked] for new developments on the application of sip