Specifications

Engineering Guidelines
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In smaller networks, the definitions of the boundaries may become a little blurred. However, even
in these smaller networks, plan a tree-type structure between the 3300 ICP and the phones.
Daisy-chaining a number of switches is not recommended since all switches become involved in
connections from one end of the chain to the other. Layering will reduce unnecessary traffic.
For more specific information on network configurations, see the 3300 ICP Technician’s
Handbook.
Operating with SX-2000 and Third-Party PBXs
In situations where the 3300 ICP is going to be inter-working with an SX-2000 or third-party
PBX, there is a risk of echo and voice quality problems if the equipment is not correctly
connected to the PSTN.
The specific area of concern is with connections to the PSTN over analog (LS) trunks. The
3300 ICP has advanced capabilities for connecting to analog trunks, which third-party PBXs
and the SX-2000 do not have.
To avoid problems, the 3300 ICP should be used to make the connection to the PSTN over
analog trunks. The SX-2000 or third-party PBX should not be used to connect analog trunks;
instead, the SX-2000 or third-party PBX should be connected to the 3300 ICP via digital trunks.
Mitel's Line Measurement Tool should be run during installation so that the 3300 ICP employs
the correct analog trunk parameters. This will ensure proper matching between the 3300 ICP
and the analog trunk and result in optimum audio quality.
If the above recommendations are not followed, there is a high level of probability that calls
placed from VoIP phones to the PSTN via analog trunks will experience distortion, echo, and
very poor audio quality.