The answer depends on the SIP provider. We’ll answer this question with Broadvox capabilities:
- The ability to provide a primary / secondary configuration to two SIP trunks.
- The ability to load balance to multiple IP addresses on the customer’s end. Concurrent call sessions (per trunk) must be split between IP addresses.
- The ability to perform fail-over to a POTS line or cellular number if the SIP trunk goes down.
- The ability to automatically fail over between separate Internet connections using SIP registration.
Note: Fail-over capabilities also depend on the phone system and/or network equipment deployed. We’ve seen in work natively with some phone systems and we’ve seen additional routers that had to be installed with others. We highly recommend you test all SIP capabilities, including fail-over, with your particular brand of PBX.