Question about endpoint registration

Using 16.1 & pjsip. As far as I can tell I have an endpoint that requires registration every 60 seconds. Does the code show what margin Asterisk uses? i.e. If I specify registration=120 how long before the end of time does Asterisk send the register? My ITSP appears to get weird about this. It looks like the “standard” is when 1/2 of the time has expired. So if I specify registration=120, it registers when 1/2 of the time has elapsed and this is exactly what they are looking for but if Asterisk waits until say, 110 seconds has elapsed it may not work.

If you are referring to outbound registration from Asterisk it re-registers 10 seconds before expiration[1].

[1] https://github.com/asterisk/asterisk/blob/master/res/res_pjsip_outbound_registration.c#L242

Thanks. I had approximated it might be 10 seconds but couldn’t tell for sure.