IP-PBXs: Ready And
Waiting
by Edwin E. Mier, Kenneth M. Percy, and Kevin D. Brown
Published January 2002
Abstract:
We had a packed house for this year's BCR testing of IP telephony systems.
There are lots of products out there, and the vendor community clearly expects
2002 to see sharply accelerating demand and deployment. Maybe.
We can't speak to the state of the economy, but we can attest to the
readiness of the technology. Test slots were filled on a first-come,
first-served basis, and the results of 10 tested IP-PBX systems from eight
leading vendors are included in this article:
 |
Alcatel
e-ND submitted the latest release, 4.2, of its OmniPCX 4400. |
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Avaya
submitted two systems, which share many of the same IP components and all
of the same station equipment: the mid-range IP600 Communications Server,
running release 9.5 software; and a Definity G3, model SI, running the new
release 10 software. |
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Cisco
brought in the latest version, 3.1(1), of its AVVID/CallManager IP
Telephony System. |
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Mitel
Networks delivered two systems: its low-end 3100 Integrated Communications
Platform (ICP), version 3.0; and its mid-range 3300 ICP, also version 3.0.
These two systems employ and support all the same station equipment. |
|
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Shoreline
Communications sent us version 3.1 of its Shoreline3 package. |
|
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Siemens
Enterprise Networks Division submitted version 1.0 of its Hicom 150 H IP
Convergence Platform. |
|
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3Com
delivered the latest rendition, version 4.0.1, of what it now calls the
3Com SuperStack 3 NBX. |
|
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Vertical
Networks brought in version 4.0 of its InstantOffice 6000, which, while
still a lower-end offering, now supports up to 180 stations. |
Reviewing these 10 IP-PBX systems reveals broad product differences in almost
all respects. While the capacities of several of the systems have increased
substantially over the last year, users will generally categorize these as we
have, with high-end systems (over 1,000 stations) from Alcatel, Avaya, Cisco and
Shoreline, mid-range systems (200 to 1,000 stations) from Avaya, Mitel and 3Com,
and low-end systems (under 200 stations) from Mitel, Siemens and Vertical.
All the vendors offer new and unique applications and features that exploit
the characteristics of the underlying IP infrastructure. The most common ones
include softphones, unified messaging systems and distance-independent
call-center systems.
There is widespread support for VOIP standards in today's IP-PBX products,
notably H.323, but variations in implementations continue to frustrate
interoperability. Also, the standards do not now address all the telephone
features that IP-PBX vendors need to implement, leading to some proprietary
protocol "extensions" with virtually all the systems.
With only isolated exceptions, though, the systems all proved they deliver
excellent performance. In our estimation, users of these systems' IP phones
and/or VOIP processing would not be able to distinguish call quality from
predecessor TDM/circuit-switching systems.
