acejavelin

Analogue PBX is pretty vague but I will try to give you some general information and some options in order of preference.

Option 1: Connect together via a T-1 or PRI, just set one as Network Master and the other as a Slave and send digits as needed back and forth

Option 2: Connect via Analog E&M Tie Lines, this would require a peripheral bay and E&M trunk cards on the 3300 and not all other PBX's support them. Call routing and setup is similar to T-1.

Option 3: Use LS and ONS ports. Connect a ONS port on the other PBX to a LS Trunk port on the 3300 and take a ONS port off the 3300 and connect to an LS Trunk port on the other system. Remember that you are now goverened by standard analog LS trunk rules.

Option 3 can get interesting but can work well if you have enough ports available, let me explain, say PBX-A has ONS x1200 tied to PBX-B LS trunk port, when someone on PBX-A dials 1200, it will ring into PBX-B as if it was an analog LS Central Office line, you need to set an answer point (extension, hunt group, Auto-attendant, etc.). BUT the other way will work OK, you can send a call OUT of PBX-B on an LS Trunk port and just have ARS dial the extension number on PBX-B's station port (it is connected to a ONS port and sees digits as if dialed by a phone).

As far as specific programming, it all depends on what the capabilities of the other end are, but treat the extensions like CO lines and program accordingly, if they have Caller ID enable CLASS on the trunks. When you setup the extensions in either PBX, make sure to use Positive Disconnect (other manufacturers sometimes call it something else) to ensure the ONS extension to LS Trunk ports don't get "hung" and fail to disconnect.

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