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Connecting PBX to Router


We have been tasked with migrating a Lucent 6000 PBX extender from its conventional WAN connection over a channelized voice-grade T1 to a Cisco 2821 ISR router.

Basically, what we are being tasked to do is migrate the T1 connection from the PBX extenders to the WAN interface on the Cisco routers (no biggie), and then connect a Cisco 3560 switch to the router's LAN interface, and then connect the PBX 6000 to the switch. SEE DIAGRAM.

My question involves how one goes about making the connection from the extender to the switch. The interfaces on the 6000 extender are 1) and Amphenol that faces some 66 blocks and eventually the phone sets; 2) a DB-25 WAN interface that connects to a CSU/DSU; and 3) an ethernet conenction that is supposedly used for management purposes only and "optionally" in a VoIP deployment.

So, it seems obvious that the ethernet interface will have to be the one facing the switch. But does it get configured as a trunk, a routed interface, or what?

I am envisioning the ethernet interface of the 6000 to be routed and placed on the same subnet with the router's LAN interface. And, of course, between the two of them is the 3560, with each one of its switchports configured for the same vlan - one switchport facing the 6000 and the other facing the routers LAN interface.

Does this make any sense at all????

Lastly, what is a PVDM module and what exactly gets plugged into it? How does it fit into this scheme of things that you see on the attached drawing?

Thank you to anyone who can help us!

Hall of Fame Super Gold

Re: Connecting PBX to Router

Hi, to save you time and potential frustration when doing this your first voip project, recommend you hire a reputable professional, for example you can contact myself at the address present in my profile.