Keepalive vs re-REGISTER
Hello,
We have a SD4500 configured as an access-SBC. The UAs being used are VoIP apps running on Android/IPhone via UDP or TCP (and TLS in the nearby future, SSM module is already available).
Currently registration caching is enabled and HNT is achieved by letting the UA re-register itself (expire time is set to 60 seconds).
Now our customer would rather make use of keepalive SIP messages (4 bytes msg) being send by the UA instead of a RE-REGISTER every 60 seconds. It is assumed a SIP REGISTER message consumes more battery-power than the keepalives.
Anyhow; currently the keepalive SIP messages send by the UA is via UDP and contains the following data: 0d:0a:0d:0a. The message is sourced from a random port and destined for 5060 on the Acme SIP-interface and send every 30 seconds.