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Scenarios 637
The experts at RouteitRight agree that converging the two networks is the way to go. There are
several ways to do this. What would you recommend? How would you plan the conversion?
Answer to Scenario 1
Getting Championship Soccer's network ready for voice and data should happen in stages. The
first stage, toll bypass, allows voice traffic to bypass the PSTN and be routed to the IP network.
Both PBX and routers remain in place as the network is migrated in phases from voice and data
to one voice/data network. The second stage is the IP telephony phase: IP phones, voice-capable
computer applications, and Web-based multimedia applications that integrate voice and data to
the desktop.
What type of voice over packet should be used for Championship Soccer, Inc.? VoIP? VoFR?
VoATM?
In this case, you aren't running ATM. So VoATM can't be considered. This leaves you with
VoFR and VoIP.
VoFR is the circuit that most interoffices have adopted to carry voice traffic. The standards for
VoFR have been in place for several years. So VoFR in general has greater vendor
interoperability and is a better-tested product. VoFR uses less bandwidth than VoIP. A call that
has been compressed using G.729A uses about 8 Kbps. When the FR overhead is added, the
bandwidth consumption increases to just under 11 Kbps. VoFR is an excellent WAN transport
technology, but it cannot be deployed over LANs or to the desktop.
You should select VoIP because it is the only choice that can be completely deployed to the
desktop for the final stage. VoIP can leverage the Internet and intranet infrastructure in terms of
routing and making any-to-any calls over the Internet. Leveraging the emerging employee
productivity, customer care, e-commerce, and business efficiency multimedia applications
requires VoIP.
Figure 16-11 shows the Championship Soccer network after the first phase of toll bypass.
87200333.book Page 637 Wednesday, August 22, 2001 1:41 PM