Mitel MIVOICE OFFICE 250, Installation And Administration Manual

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Specifications
95
• Wireless IP phones 8664, 8665, and 8668.
• IP gateway trunks, neither Station Initiation Protocol (SIP) nor Media Gateway Control Protocol
(MGCP).
• SIP phones.
• Audio and Web Conferencing (AWC)
52xx/53xx phones do not support the Automatic Network Address Translation (NAT) address type.
In DB Programming, you must select either Native or NAT for private and public networks. Refer to
the
MiVoice Office 250 Features and Programming Guide
, part number 580.8006, to configure the
NAT address type.
System Resources with DEI
Installing up to four DEI units in a MiVoice Office 250 increases the number of resources available
for each of three DEM-16s.
• In 2-DEI mode, the system has the same functionality as pre-v3.x except for the on-module
resources. You can equip up to six DEMs on two DEIs. Each DEI has 96 timeslots available for
48 digital telephones and each DEI also provides additional features such as OHVA, dual-SLAs,
and MDPMs. Each DEM provides four DTMF receivers.
• In 4-DEI mode, there are 48 voice channels to each DEI; this provides one voice channel per
digital telephone. Features that require a second voice channel, such as OHVA, MDPM, and
dual-SLA, require special attention. Enable these features using the current methods; however,
these features use a voice channel that could otherwise be used by a telephone on the same
DEI. DB Programming counts the time slots used by these features and enforces the maximum
timeslot limit for each DEI.
• Features that require a second voice channel, dual-SLAs, OHVA, and MDPMs are affected when
expanding DEI capacity. When in 4-DEI mode, do not overallocate a DEI with these features.
Enabling features that require a second voice channel will likely reduce the maximum phone
capacity in 4-DEI mode.
• The DEM four DTMF receivers, eight caller-ID transmitters, and four caller-ID receiver DSP
resources will be disabled in 4-DEI mode. The DEM 16 speakerphone resources will still be
available to digital keysets connected to the DEM in this mode. The loss of the caller-ID trans -
mitters and receivers are offset by using the DSP for these functions. The four DTMF receivers
on each module are offset because the Dual T1/E1/PRI Module has DTMF receivers built into
each channel.
A DEI is “slightly over allocated” if it has more than 48 time slots programmed and the system is in
4-DEI Mode. It is “extremely over allocated” if it has more than 53 time slots programmed and the
system is in 4-DEI Mode. DB Programming should (in most cases) prevent the system from ever
becoming extremely over allocated.
When programming, there are two basic cases where a warning or error message related to time
shot usage may appear:
• If the time slot values for a DEI are between the overallocated (53 time slots) and allowed (48
time slots), you are notified that you have entered a '”blocking scenario” and you can choose
whether to continue changing the time slot usage.