[Asterisk-Users] Recommendations for Asterisk + Lucent Merlin Legend PBX Topology

[rsenykoff at harrislogic.com]

Hello all.

I've got management convinced that I can save them a bunch of money between
our sites by hooking up Asterisk to our existing PBXs in such a way that
intra-office calls route through Asterisk.

I'm a developer that's new to telephony and need to figure out how I can
hook up Asterisk such that calls to other sites get routed from the
existing PBX through Asterisk, while all other calls get routed to the
outside world normally.

We have a Lucent Merlin Legend PBX. Can I hook it up this way:

              |-----|
--------
----------    |     |-----|----------|
|----------|------| PBX  |
|Phone T1|----| PBX |-----| Asterisk |-------------WAN----------------|
Asterisk |------|      |
----------    |     |-----|----------|
|----------|------|      |
              -------
--------
              |  |  |
|   |   |
             analog phones
analog phones

The idea is that I set the PBX to use several lines for the same extension.
So you could make that a single digit '5' extension or something. Then
Asterisk picks up and asks for the WAN extension which would route to the
correct Asterisk box on the other end, which would also have multiple lines
to the PBX.

Is it possible to configure PBXs in such a way? i.e. that multiple lines
are assigned to the same extension? Is there another way I should be
researching doing this? My reasoning for multiple lines is to allow X
number of simultaneous calls between sites.

TIA!
-Ron