[asterisk-dev] SDP Manger feature

[Canuck .]

Thank you for the response.  If I understand that correctly it would be 
for Asterisk behind NAT.   My scenario is the other way around.  
Asterisk on public IP and extension(s) behind NAT.


On 2016-11-02 7:27 AM, Matt Fredrickson wrote:
> On Tue, Nov 1, 2016 at 10:00 AM, Canuck . <canuck15 at hotmail.com> wrote:
>> Has there been any discussions of adding an SDP mangler to Asterisk? One
>> possible application I can think of is allowing directmedia to peers that
>> are behind NAT. It's probably more difficult than just SDP mangling but that
>> is probably a good start. I am sure it would have other uses as well.
>>
>> Essentially, I am look for an equivalent to the SDP mangler available for
>> Kamailio without having to install Kamailio and integrate it with Asterisk
>> just for that feature.
>>
>> http://www.kamailio.org/docs/modules/4.1.x/modules/mangler.html
>>
>> For directmedia use, it would basically use the same values as
>> nat=force_rport, comedia does. So it would replace the SDP port and IP with
>> those values if it detects a private IP address.
>>
>> Before I start experimenting with the Kamailio module, am I on the right
>> track with this?  How feasable is this as a new asterisk feature?
> If your purpose is for providing address rewriting for purposes of NAT
> (on pre-mapped and opened port ranges) you can already do this in
> pjsip.conf on the transport object:
>
> [transport-udp-nat]
> type=transport
> protocol=udp
> bind=0.0.0.0
> local_net=192.0.2.0/24
> external_media_address=203.0.113.1
> external_signaling_address=203.0.113.1
>
> You only need to set your localnet to a proper internal value, and set
> your external_* addresses to whatever your public IP is set to.
>
> Hope that helps!
>