[SR-Users] RFC: rtpproxy and a=nortpproxy:yes

[Daniel-Constantin Mierla]

Hello,

I am looking to get some feedback on some issues I noticed more and more
lately.

Apparently some SIP devices (media servers, phones, ...) are keeping the
"a=nortpproxy:yes" line in SDP when replying to an INVITE that contains
such line.

[Alice]  ------> [Kamailio+RTPProxy] ------> [Bob]

The 200ok response from Bob has "a=nortpproxy:yes" in SDP.

By default, that line in SDP makes the rtpproxy not to engage itself
anymore in rtp relaying, and as a result things like no audio or one way
audio happens.

Anyone else encountering such situations? If yes, what are the devices
with such behaviour? So far I noticed with some FreeSwitch and Snom --
none of them I can control, so there might be a specific configuration
of those devices, not something by default there.

The solution is to set:

modparam("rtpproxy", "nortpproxy_str", "")

and use flag 'r' for rtpproxy_manage() if the IP in SDP is not a private
address.

I already updated the default config for master to use flag 'r' if the
SDP media IP is not private, wondering if nortpproxy_str should be set
to empty in kamailio.cfg (or made empty as default in config).

Cheers,
Daniel

-- 
Daniel-Constantin Mierla
http://twitter.com/#!/miconda - http://www.linkedin.com/in/miconda
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