Through our experiences of installing and testing several manufacturers' IP gateways,
we've learned some truths on the matter. For example, black-box gateways tend to perform
better than PC-based gateways and deceased latency or increased feature sets exist at the
sacrifice of sound quality. The initial cost issue also supports the advantage of the
Multi-Tech's MVP200 MultiVoIP is no exception, but its uniqueness stems from its
compromises. It doesn't cost much, there is exceptional sound quality, and the
documentation makes it simple to install - but the latency, feature set, and scalability
are only of average quality. Do not buy this gateway if you're planning large-scale voice
implementations. However, for smaller companies or for companies who intend to use IP
mostly for fax purposes, the MultiVoIP should be a strong consideration.
When we test gateways, we order them in pairs, and we install them on a "clean"
and manageable network so that other factors don't interrupt. This network consists solely
of the two gateways and our Hammer IT testing system, with all three devices on one hub.
This ideal, laboratory environment is obviously not a real-world test, but by comparing
every gateway in the same fashion, we can begin to compare them to each other and to the
The bottom line on the MultiVoIP installation process is this: If we could give a
higher grade than 5, we would. Here's why:
When installing gateways, major issues include PBX integration and complexity. The
MultiVoIP's two ports are configurable for FXO, FXS, and E&M styles. To minimize
external variables that would differ from system to system, we eliminated the step of
connecting a PBX between the outside world and our network, opting to test only the
intranet telephony. Unlike other CTI products we test, speed is not an issue when
installing gateways, but we must mention it here because we've never seen a pair of
gateways successfully installed in less than half a day before. Conversely, the MutliVoIPs
were working in less than thirty minutes, complete with telephone extensions mapped to IP
addresses, multiple voice coders installed and our Hammer IT system communicating with the
gateways without obstacles. For the issue of requisite man-hours during installation, the
MultiVoIP is the best we've ever seen.
Our favorite installation aspect was the simplicity, however. System administrators
need not be trained interconnects; a mid-level MIS manager can do the job just as well.
Each gateway has five connections including an RJ-45 Ethernet port, an Ethernet-to-serial
port connection to connect the controlling PCs, AC power, two FXS ports for analog
devices, and two FXO and E&M ports for connecting analog lines. When the cabling
process was complete, we switched on both systems, and the gateways began a POST process
that lasted just a few minutes. When the boot LEDs go off, software installation can
According to Multi-Tech, the software can run on any Windows 95 or 98 machine, but
common sense and experience tells us never to attempt a gateway environment on non-NT
platforms. The computers we used were identical Pentium IIs running at 300 MHz, one with
64 MB RAM and one with 96 MB. Both systems ran NT 4.0 Server with Service Pack 4.
The MultiVoIP software installation is for configuration and maintenance purposes only
- it doesn't need to run while the gateways are in use, which is why we still classify the
actual gateways as black boxes instead of hybrid systems. The gateways themselves are
quite small and weigh just 2 pounds each.
During setup, administrators enter data for the COM ports, IP addresses, subnet masks,
and gateway addresses. Configuring the gateways involves a master/slave relationship and
the usual proprietary routing tables. The documentation for this installation is very
good, and every step includes its own screen shot. As we stated above, this product is a
winner for its installation. It would have been difficult not to get these gateways
working on the first try.
A printed quick start guide and an online .PDF user's manual are included. Every step in
the installation was completed using just the quick start guide, which speaks highly of
the Multi-Tech technical writers. The .PDF manual includes six chapters, three appendices
and a glossary. Topics include an introduction, installation, software configuration,
software features, remote configuration, support, TCP/IP, cabling, and regulatory
information. The glossary includes about 250 industry terms, and is a nice feature,
especially for novices. Clearly, the manual is written with the beginner in mind.
Step-by-step instructions, diagrams, and simple English explanations are abundant here.
Important features found in most gateways (or available as third-party modules) include
gatekeeper/billing software, security/data encryption, remote/Web-based management, and
advanced rules-based calling patterns with LCR. Our edition of the MultiVoIP does not
offer the gatekeeper/billing services, but a newer upgrade available when you read this
will have primitive versions of these features. Our version did include remote management,
accessible with a Telnet session or through an IP connection. Other MultiVoIP features
- Ability to download firmware and vocoders.
- Address book.
- SNMP management.
- Pulse/Tone dialing with regional options.
- Adjustable inter-digit dialing time.
- Tone and Wink options.
- Auto Call.
- Fax baud rate/volume.
- Silence compression/error cancellation.
- Hunt groups.
- Ethernet/proxy server setup.
There are 22 vocoders to choose from, spanning five vocoder families, including G.711,
G.726, G.727, G.723 and NetCoder. We know that there is a direct correlation between
packet latency and speech scores; measurements are taken using time-stamping and the ITU's
Perceptual Speech Quality Measurement system. (Tolerable PSQM scores for IP gateways
include anything below a 5; good scores include anything below a 4; exceptional scores are
3 and below. Scores on the PSTN usually fall well below a 3.)
Although some of the proprietary NetCoder compressions may have worked better, we chose
to test the MultiVoIP with the G.723.1 compression at 6.3 Kbps because the G.7xx family is
more common and more easily compared between products. Multi-Tech also provides a 5.3 Kbps
version of the G.723.1 compression, but that ratio would cause the latency figures to be
too high to be useful. At 6.3 Kbps, spanning a 70-call sampling, the PSQM scores were 2.63
for children's voices, 2.64 for adult males, and 2.25 for females. These numbers are
impressive, but conversely, the latency average for the same sampling was 134.5 ms. That
figure is good compared to PC-based gateways, but quite poor for a black-box system.
Overall, these results matched our hypothesis. Smaller samplings with lesser compressions
(for example, 8 or 16 Kbps) successfully decreased the latency but made the PSQM scores
To develop a test of the fax capability, we removed the telephones from both of the
MultiVoIP FXS ports and replaced them with fax devices. One device was a Brooktrout 2-port
TR-114 series fax board; the other was a regular fax machine. At the computer where the
fax board was installed, we initiated a sample DOS fax test created by Omtool (we were
testing their Fax Sr. program at the time). The sample fax successfully navigated itself
out of the fax board, to a MultiVoIP, across the network, to the second MultiVoIP, and to
the fax machine. Success! We didn't save any money, of course, because both fax devices
are here in one office - not exactly a toll call. Even our cross-town office is a local
call, so we did not have a long-distance path with which to test. If the call had been
long-distance, the benefits would be that much more tangible.
We have no issues with the overall usability of the MutliVoIPs. Standard Windows
conventions are used throughout the GUI; dialing plans, routing tables and security/user
features are easily configured; and there is no requirement to have any software running
for the gateways to function normally. We expect larger versions of the gateway, such as
4- and 8-port versions, to be available in the future.
ROOM FOR IMPROVEMENT
We're told by Multi-Tech engineers that many of the same suggestions we have are already
incorporated for the minor release available when you read this. These modifications
include FXO-to-FXO capability, with a customizable disconnect tone, and with additional
disconnects with current loss or programmable silence time-outs. There will also be
advanced call logging, advanced password security and user authentication, and a dynamic
jitter buffer, which is an important feature that's conspicuously missing from the current
firmware. We're also told that there are efforts to decrease latency, to increase fax
reliability and to improve the error cancellation algorithm. Still, we'd like to see more
advanced sample applications included, we feel that the features section of the user's
manual could use some re-organization and administrator's tutorials, and the online help
feature needs a major upgrade. Help topics, although they are context-sensitive, could be
linked to relevant topics from the online user's manual. There are some shortcomings in
the complexity/customizability of the routing tables. Features we'd like to see include
support for conference calls, an automated way of managing daisy-chained gateways, and
screens like the ones for channel and IP statistics need improvements to make their
data more meaningful.
For smaller organizations with a tight budget and voice/fax needs, the MVP200 MultiVoIP
system should be considered. It is easy to install, it is inexpensive, it is easy to
upgrade, and it is highly functional. However, it is not H.323 compliant, the
documentation is only average, and its feature set hits on some key Internet telephony
issues but misses on others. The MultiVoIP comes very, very close to earning our Editor's
Choice award, but it's just not yet powerful enough. Future versions could cross the line
by retaining the simple installation process and low cost while adding scalability,
management, and some of the technical features outlined above.