|Summary:||ASTERISK-19515: Need hooks for resource to leverage for NAT hole poking for media streams|
|Reporter:||Philip Prindeville (pprindeville)||Labels:|
|Date Opened:||2012-03-11 15:47:08||Date Closed:||2012-03-13 10:38:41|
|Environment:||This is applicable when Asterisk is running co-resident on a NATting gateway.||Attachments:|
|Description:||It is useful for Asterisk to be able to control NAT mappings for inbound media streams, whether it is running on a NATting gateway or not (as it's possible that the streams terminate on handsets that are behind a different gateway in the case where Asterisk is hosted behind the gateway or the handsets are behind a different default gateway).|
There are several scenarios where this might be useful:
(a) Asterisk is running on a Linux gateway itself, and a resource module (e.g. res_iptc) calls into libiptc directly to open/close NAT holes;
(b) Asterisk is running on a Linux gateway is in (a), and a resource module uses fork()/exec() to invoke iptables to create new open/close NAT holes (this avoids tainting Asterisk licensing);
(c) Asterisk is running behind a UPnP gateway (or even on that gateway) and uses UPnP IGD calls to open/close NAT holes (this is the most flexible but lease robust mechanism);
This requires Asterisk to provide 3 hooks NAT holes for media streams:
(1) make a new hole (as when a SIP INVITE is seen);
(2) destroy an existing hole (as when a SIP BYE is seen);
(3) replace the parameters on an existing hole with new parameters (as when a SIP REDIRECT is seen to a new end-point also behind the same gateway, i.e. on the same collection of local LANs), i.e. do a make-then-break mapping;
This is not only applicable to SIP, but to other protocols that support separate signalling and media streams.
|Comments:||By: Philip Prindeville (pprindeville) 2012-03-11 15:53:40.060-0500|
By: Philip Prindeville (pprindeville) 2012-03-11 15:54:41.045-0500
And so it's clear, I'll write the version for scenario (a) once the hooks become available... though I might need a little help debugging the test cases as I'm not a SIP guru.
By: Matt Jordan (mjordan) 2012-03-13 10:38:33.980-0500
Features requests are no longer submitted to or accepted through the issue tracker. Features requests are openly discussed on the mailing lists  and Asterisk IRC channels and made note of by Bug Marshals.
If you would like to submit a patch for this feature, please contact a bug marshal and we can re-open this issue.
By: Philip Prindeville (pprindeville) 2012-03-13 11:48:21.730-0500
This feature was extensively discussed both on IRC and the mailing list, and the resulting Mantis bug referenced was created:
It then unfortunately stalled because of feature-creep: access control lists, etc. started to creep in, etc.
This was an attempt to resurrect the same bug but focus attention to what the original intention was: a way for a resource to hook into NAT hole requests for media streams.