Switching to VoIP

This is the Title of the Book, eMatter Edition

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

Key Issues: Network Infrastructure for VoIP

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Key Issues: Network Infrastructure for VoIP

• The topology of a VoIP network rides atop that of an IP network.

• Your IP network layout affects where you locate voice resources on the network

and how resilient voice services will be to failure.

• Hub and spoke networks offer little remote redundancy but result in cheap con-

nectivity.

• Meshed networks offer redundancy, but result in more expensive connectivity.

• Peered networks offer the least-expensive connectivity but are often the least

capable of yielding positive results with IP telephony because call paths across

peered networks are prone to latency.

• When choosing a location for a voice resource like a PBX server or media gate-

way, locate to conserve bandwidth, to save money, and to gain long-term capa-

bilities, not because of superficial or short-term conveniences.

• The best way to survive a power failure is battery backup, but using multiphase

power from the electric company can somewhat reduce the risks of power loss.

• PSTN trunk failures almost always incur some manual failover, whether it’s call-

ing the phone company to get a line forwarded or physically juggling trunks

around to compensate for a downed trunk.

• IP-based trunks (VoIP trunks) can be more easily failed