Switching to VoIP

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At a minimum, at least two VoIP devices (such as an IP telephone and a VoIP server

or two VoIP servers) and at least one form of connectivity are required by all VoIP

solutions.

Like the network, VoIP is a conversation-oriented technology. Its protocols are sim-

ply rules that devices and software must follow in order to carry on the conversa-

tions required to make VoIP applications work—that is, to carry each human speech

conversation. Each VoIP protocol set (H.323 and SIP are the two big sets) has its

own rules that enforce proper conversation, just as Congress has a parliamentary

procedure that enforces its debates. The biggest rule is the definition of VoIP’s mini-

mum requirements: two or more TCP/IP hosts using one common protocol and con-

nected data links.

Network Convergence

When you support only one transport (in VoIP’s case, TCP/IP) for all networked

applications, including telecommunications, you’ve achieved complete convergence.

The more you leverage your TCP/IP network to support voice and multimedia tele-

com apps, the more you converge. Theory tells us that convergence increases admin-

istrator productivity, and experience tells us that support costs drop the more voice

and data networks are converged.

Convergence isn’t something that has ...