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Chapter 13: Network Infrastructure for VoIP
WAN Layout
Hub and spoke
If your WAN is a hub and spoke layout, you most likely have a single (or a few), cen-
tralized data center where all of your business locations’ connections with the rest of
the network are made. Hub and spoke networks, like the one at the lower left in
Figure 13-2, allow for easy central network administration and often have lower
facilities costs than other layouts. In hub and spoke networks, all remote locations
connect directly to the data center without any intermediate hops.
The benefit of hub and spoke layouts to VoIP is that they minimize latency because
there’s only one hop between the remote office and the data center (where the soft-
PBX and primary switching equipment are). Other layouts may contribute more to
latency than hub and spoke does. If there’s a drawback to the hub and spoke
approach, it’s that there’s a single point of failure on the WAN—the data center.
Figure 13-2. WAN layouts, clockwise from top left: partially meshed, circular peered, linear peered,
hub and spoke
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