Specifications

Spectralink 84-Series with AudioCodes Gateway and Avaya Communication Manager: Interoperability Guide
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Additional Mediant Gateway s can be added to increase capacity using the same formula as
above.
In almost every scenario, the trunk interface voice channels should not have a 1:1 mapping with
telephony extensions. Instead the trunk interface is configured to dynamically support more SIP
end points than the actual channels. In fact, tying channels to specific extension is undesirable
as it prevents features requiring more than one active line such as transfer, forward, hold, etc.
Typical business handset usage during busy hours requires somewhere between 0.1 and 0.2
voice circuits per user/extension to the PBX. In other words each voice channel to the PBX from
the Wi-Fi handset users can support between 5 and 10 users. In more traditional telephony
terms, each user requires between 100 and 200 milli-Erlangs of capacity to the PBX. Using the
100 milli-Erlang calculation, 230 handsets could be supported per T1 PRI (which has 23 voice
DS0 channels). Each Mediant Gateway has a simultaneous registration maximum of 600 so
here again the usage factor is critical to accurate deployment capacity.
Features Tested and Validated
The Spectralink 84-Series handsets are state of the art SIP endpoints. The extensive feature set
and configuration possibilities create a custom telephony environment only available within the
SIP protocol. Many of these features, if not most, are available within this solution. However
some features do not survive the translation from one protocol to another and cannot be
expected in this hybrid environment. See the table on the next page and the footnotes that
follow.