Capacity and Limitations
Capacity
It is possible to initiate more than one emergency IP networking route for emergency calls, for example, one for each branch office.
Limitations
Limitations on Dial-Back Capacity:
If H.323 is used, only the information about the last calling party to dial the emergency number will be stored; therefore, the emergency center can only dial back the last calling user. This limitation is for calls from logged-on and logged-off IP telephones.
If SIP is used, information about one calling party per domain will be stored.
Limitations on the H.323 Access Point:
The IP networking route for emergency calls from logged off IP telephones can only be initiated in a unique LIM. The trunk lines for this route cannot be defined in different LIMs.
Limitations on Logged-Off SIP Telephones:
It is possible to make emergency calls from logged-off Mitel 6900/6800/6700 telephones and most logged-off third party telephones.
Mitel 8000i video terminals cannot make emergency calls when logged-off.