Switching to VoIP

This is the Title of the Book, eMatter Edition

Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.

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Chapter 13: Network Infrastructure for VoIP

be required. It’s quite common for voice mail and email servers to be installed in the

same rack or to be running on the same PC.

Since we’re talking about layout, all of these issues must be taken into account when

looking at how your VoIP network will overlay your IP network layout. Is there

enough bandwidth to support the necessary loads between all endpoints? Would

adding a new connection solve a capacity problem imposed by VoIP, or would it be

better to place a PBX somewhere to solve the problem? Which solution would be

more cost-effective? Is your vision of Voice over IP even feasible given today’s load

on the network? If it’s a peered network, would the outlook for VoIP be better with a

hub and spoke layout or a few new mesh links? How would such a change affect

other network systems?

Don’t locate for convenience

The VoIP network ought to drive the IP network design. A PBX shouldn’t be placed

in a particular location because “that office already has a server rack and a UPS” or

because “that’s the office where the old phone system is.” Ultimately, while these

issues are an influence, they can’t be deciding factors in locating VoIP resources. The

VoIP network’s design must not be retrofitted around the current network’s preexist-

ing ...