[sr-dev] [kamailio/kamailio] uac: registration refresh should in half time of expire (#2765)

[Surendra Tiwari]

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#### Description
Currently re-registration is not happening in half of expire time. sometime its reaching near to expire time then sending re-registration. usually sip servers expect re-registration to happen in half of expire time.
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You can view, comment on, or merge this pull request online at:

https://github.com/kamailio/kamailio/pull/2765

-- Commit Summary --

* uac: registration refresh should in half time of expire

-- File Changes --

M src/modules/uac/uac_reg.c (2)

-- Patch Links --

https://github.com/kamailio/kamailio/pull/2765.patch
https://github.com/kamailio/kamailio/pull/2765.diff

[Henning Westerholt]

Hello, thanks for the pull request. If I do not misread the standard ([link](https://datatracker.ietf.org/doc/html/rfc3261#section-10.2.4)), there is no particular requirement for your change.
Have you tried to just set a lower reg_retry_interval? E.g.:
- reg_retry_interval: 180
- expires: 360

[Surendra Tiwari]

@henningw reg_retry_interval is used for failed registration retry. i am looking for refreshing registration. Also just think about having multiple pbx that expect different expire then reg_timer_interval will not work. Also what changes i made that's apply to every where.

[Henning Westerholt]

I quoted the wrong parameter, i meant the reg_timer_interval:
https://kamailio.org/docs/modules/devel/modules/uac.html#uac.p.reg_timer_interval

[Henning Westerholt]

The refresh threshold could be of course configured with a module parameter, keeping the current behavior as default.

[Surendra Tiwari]

yeah i checked this too reg_timer_interval but this is not getting apply if kamailio is sending register to different pbx that are expecting different expire time.

[Daniel-Constantin Mierla]

Doing registration refresh at the half of the expires interval is not a common practice, nor a requirement from SIP RFC, like @henningw pointed out. I haven't noticed such behaviour by sip phones, either. I second that such behaviour needs a module parameter to control it, default behaviour should stay like it is now.

[Surendra Tiwari]

@henningw @miconda agreed its not hard core requirement from sip rfc , i will setup an module parameter for the same and will keep default behaviour as it is. :-)