[SR-Users] Is Media Release (signaling only) possible in Kamailio?

[Alex Balashov]

Re-read the piece of the article related to "RTP latching":

http://blog.csrpswitch.com/server-side-nat-traversal-with-kamailio-the-definitive-guide/

In order for RTP to reach a NAT'd endpoint, all other things being
equal, the other party has to do RTP latching. This is true of both
inbound and outbound calls. Failure to do it will result in one-way
audio where the NAT'd party can transmit but cannot receive. 

As far as identifying who is doing that latching, that's not clear from
your description. Some carrier media gateways do it, in which case you
can get away with not having an RTP relay in the middle. Most carrier
media gateways are designed for wholesale-ish peering and don't, as a
matter of policy, but some do. Or you could have some near-end solutions
at work of which you're not aware. 

It's also not clear whether you've definitively removed all rtpproxy
invocation from your Kamailio config, in both directions. But if you
haven't, I'd start there, and given your statement that you don't really
want to be in series to the RTP path, figure out what exactly doesn't
work. Then add rtpproxy as necessary. Beware the distinction between
inbound and outbound call flows.

-- Alex

On Wed, May 09, 2018 at 09:15:48PM +0000, KamDev Essa wrote:

>  Well then why does Inbound (from carrier to NATed UA) call work. Kam is doing something clever there. Why not when sending the call out. 
> KD  
>     On Wednesday, May 9, 2018, 4:34:55 PM EDT, Alex Balashov <abalashov at evaristesys.com> wrote:  
>  
>  Oh, the UAs are NAT'd? Yeah, you're going to need something clever in the middle that can do the RTP latching, then. 
> 
> -- Alex
> 
> --
> Sent via mobile, please forgive typos and brevity.  

-- 
Alex Balashov | Principal | Evariste Systems LLC

Tel: +1-706-510-6800 / +1-800-250-5920 (toll-free) 
Web: http://www.evaristesys.com/, http://www.csrpswitch.com/