Switching to VoIP

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VoIP Trunks

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If you have T1 links that have very long contract periods remaining,

you might have to keep them in place even if your endgame is to

replace them with VoIP-based trunks. Some phone companies will

assess a hefty termination liability fee if you cancel your T1 lease

before it’s up!

VoIP Trunks

As you know, a VoIP trunk uses digitized voice in IP packets to link two PBX serv-

ers. VoIP trunks can replace legacy trunks only when the two PBXs being linked are

VoIP-enabled. A VoIP trunk could run between two IP-enabled PBXs, like the Avaya

S8700 and a Nortel Meridian, or between two legacy PBXs that have outboard VoIP

media conversion. Outboard conversion devices, like Cisco media gateways, allow

legacy PBXs to connect to the local Ethernet network and perform the voice packetiz-

ing for the VoIP network since the PBX can’t on its own. (The cost of outboard con-

version often helps build the case for using VoIP-enabled or native VoIP softPBXs

instead.)

Like other IP protocol families, VoIP can be tunneled within VPNs and GRE (generic

routing encapsulation)point-to-point tunnels. By now, you know it can be routed,

switched, and load-balanced. These qualities, inherited from the Internet-like net-

works that came before it, give VoIP’s trunks greater flexibility than legacy trunks. ...