ip phone business

[Mary]

when we pick up the ip phone and try to call remote branch office number, it is always busy, there is no network connectivity problem, may i know the steps to analyze from voice gateway, cucm and sip trunk?

how to troubleshoot sip trunk problem? thanks

[Mohammed al Baqari]

describe your setup. cme?cucm? single cluster?multiple clusters? how are
the sites connected? pstn?sip?

[Mary]

CUCM, no cme, single cluster, the sites are connected through IP wan, SIP voice gateway, pstn is the secondary backup in case of cucm failed