Custom timeout for RTP Session

[nganju98]

I'm working with a VOIP provider that doesn't send any packets if there's silence on the other end, i.e. if the counterparty is not speaking. This causes RTCP/RTP session timeout if the caller doesn't speak for 30 seconds.

Can I change the timeout to like 5 mins? Happy to make a PR, I can see that the code in RTCPSession uses a constant (NO_ACTIVITY_TIMEOUT_MILLISECONDS), I could make it a mutable member variable.

Or is there a better solution? Have any of you encountered this type of VOIP behavior before?

[sipsorcery]

Can't say I've heard of that behaviour before. Some NATs will delete a mapping after as little as 30s of inactivity so calls are likely to drop with that approach.

You're welcome to add a PR to add a confgurable timeout limit but please make sure the current behaviour remains as the default.

[nganju98]

Awesome! Added a PR, please let me know if I can do anything better in the PR. Also thanks for this amazing library!

[nganju98]

Thanks for the merge. Any chance you could make a point release out of it? So I can fetch it from nuget in my project? Thanks.

[nganju98]

Sorry just bumping this, is there any way we could get a point release? Like 8.0.8 just with my fix? Thanks!

[sipsorcery]

There should be a release this week. I'm waiting for confirmation of another in-train fix.

[nick-zocdoc]

Thanks for the release! Just to close the loop here, it looks like the official RTP spec supports pausing transmission during silence:

Spec is here: https://datatracker.ietf.org/doc/rfc5459/ . Do you detect this SID (silence insertion descriptor) frame? If you google it there's quite a few voip products mentioning that they use SID. Maybe if there's SID frames we should pause the timeout counter?

[sipsorcery]

No, nothing like that is done by this library. The preferred approach is to send silence. If you really wanted to stop sending RTP the event handler could just be unhooked. Definitely not recommended it there's a NAT anywhere on the path.