Lucent Technologies 101-1620-005 User Manual

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Octel Unified Messenger Concepts & Planning Guide
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101-1620-005
Evaluating the additional network traffic
Implementing Octel Unified Messenger results in the flow of voice data 
over the organization’s data network. This section provides the 
information required to calculate the additional network traffic generated 
by an Octel Unified Messenger system. This calculation is based on 
several factors, including:
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The number of voice servers in the voice mail domain (S).
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The number of ports on each voice server (P).
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The usage characteristics.
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The voice encoding rate (32 kilobits per second).
Worst-case network 
load
To calculate the worst-case network load contributed by an Octel Unified 
Messenger voice mail domain, substitute the number of voice servers in 
the voice mail domain for S and the number of ports on each voice server 
P into the following formula:
Worst-case network bandwidth = S x P x 32 kilobits per second.
For example, for a site with a voice mail domain containing five voice 
servers, each with 24 ports, the worst-case network bandwidth is 
5x24x32=3,840 kilobits per second. In addition, it is necessary to apply a 
factor to allow for the overheads applicable to the network protocols and 
options that are in operation. 
This calculation is based on the worst-case assumption that all ports are 
recording or playing voice data at the same time. It provides a calculation 
of the total network traffic potentially added, but no indication concerning 
the direction or path taken by this data. 
Dedicated 
connection
Average values will be much lower than indicated by the worst-case 
calculation presented above. However, they can still represent a 
significant load on the LAN connections between the voice servers and 
the Exchange servers. For that reason, each voice server in a multiserver 
environment should be given a dedicated switched Ethernet spur or 
switched token ring segment connecting directly into the backbone 
network.