Many small business customers employ custom calling features such as call waiting, from the BOC/LEC, attempting a more PBX-like capability. These features are not supported by SLS.
Non-ISDN signaling:
Calling party name/number information to digital station displays
Caller ID on outgoing analog station calls
Caller ID on incoming analog loop-start trunk calls
Three party conferences
Last Number Redial
Call Forwarding-Busy/Don’t Answer
No Music On Hold source or announcement playback
Call Center features, including ASAI
Connection Preserving Failover/Failback for Branch Gateways
