Specifications

System Parameters
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Mitel also tests the systems to ensure that they can withstand twice the traffic specified for the
line-size of the switch. This is to ensure that peak traffic will not impact system performance
under normal conditions.
The SX-200 ICP system also contains a traffic measurement package to help monitor actual
traffic patterns. This traffic information must be considered when additional lines and trunks are
added to an existing system. For example, information on dial tone delays may indicate a need
for additional receiver modules. Console pegs can indicate the need for additional console
positions. Trunk usage reports can indicate the need for additional trunks.
Use the traffic report figures as guidelines. Specific departments or trunks may not follow the
averages of the rest of the system. This should be understood and analyzed to ensure that
your system can meet the needs of all users.
To aid in configuring your system, the following chart can help you in determining the number
of trunks required, as well as using the System Engineering Tool. For this chart to be effective
certain assumptions have been made. If your system does not fit with these assumptions, then
consult your dealer or sales representative.
Assumptions:
a. Traffic patterns are approximately
•33% internal
• 33% outgoing
• 33% incoming.
b. Trunks are both-way, as these are most efficient for carrying traffic.
c. An adequate number of receivers are present. Rule of thumb is 4 receivers per 60
telephones.
d. Target grade of service is P.01 or the same as the level which most telephone compa-
nies provide.
To use the chart you must determine your average traffic levels for the busiest hour of the day.
Divide the number of calls for this hour by the number of telephones on your system.
• 1 call per hour = light traffic
• 2 calls per hour = medium traffic
• 3 or more calls = heavy traffic
On the bottom axis of the chart select the number of telephones in your installation. Choose
the line on the graph that represents your traffic level. The left axis indicates the recommended
number of trunks.
Special applications (such as ACD) should be highlighted to your dealer or sales representative.