372 Appendix B Branch Office engineering example
Assumptions

Equipment characteristics

Assume the Branch Office has the equipment characteristics providedin
Table39 "Equipment characteristics" (page 372).
Table 3 9
Equipment characteristics
Number Type
120 IP Phones
36 Analog (500/2500-type) telephones

Traffic characteristics

Assume the Branch Office has the traffic characteristics provided in Tabl e
40 "Trafficcharacteristics" (page 372).
Table 4 0
Trafficcharacteristics
Number Comments
6 CCS For each IP Phone, 50% of calls go to other IP Phones,
and 50% of calls go to analog (500/2500-type) telephones
and PRI trunks.
5 CCS For each analog (500/2500-type) telephone, 40% of calls go
to PRI trunks, and 60% of calls go to IP Phones.
120 seconds The average holding time for each call.
Conference traffic is generally not singled out forcalculation in traffic
engineering. When a Branch Office does not have conference capability,
conference call participants must use the LAN/WAN to reach the main
office to join conferences. However, if the traffic is significant (a rough
guide is more than 10% of IP Phone traffic), traffic should be included in
the LAN/WAN bandwidth calculation.

Required calculations

The following is a summary of the required calculations:
number of Virtual Trunksto the main office
number of Media Cards
real-time load for the Call Server
bandwidth for WAN
bandwidth for LAN
Nortel Communication Server 1000
Branch Office Installation and Commissioning
NN43001-314 01.02 Standard
Release 5.0 20 June 2007
Copyright© 2007, Nor tel Networks
.