I have a SIP gateway router at one of our sites. This gateway has SIP trunk to SIP Provider for inbound and outbound calls. There are no PRI on this SIP gateway router.
The IP Phones at the site communicate with Call Manager over the WAN.There is H.323 between the Call Manager and this SIP gatway router.
Call manager fallback is configured on this SIP gateway router.
My question is when Call manager is unavailable how will the IP Phones at the site work? Would they be able to outbound and inbound calls after fall back to SIP gateway router? What all functions are avialable to IP Phone users when on fallback? What is not available?
I have this problem too.