Is Convergence Playoff Bound?
BY ADAM ALTMAN
Itï¿½s October, and the baseball playoffs are here. This is the time
when players and teams show how good they really are ï¿½ where a pitcher
nabs the corner for strike three with the bases loaded and two outs in the
ninth or an unsung hero rises to the occasion to hit a game-winning home
run. It is also the time for each playoff contender to show that the
adversity and difficulty of the regular season has not been for naught and
that every effort to win would be put in so that they might earn the World
Series ring. And more importantly, each player would contribute to that
For many years now, the Internet telephony world has meandered in the
regular season, and the playoffs still seem a ways a way. However, we are
no longer playing the first few games of the season. We are now more than
midway through the season, and the quality of the latest VoIP equipment
has shown me that we have a winning record. To make the playoffs, we must
continue to pitch good products, hit for consumer appeal, and work
together as a team so that the industry can win.
One of the biggest areas to throw us curve balls in this industry are
issues in interoperability, where equipment from one company may not work
with someone elseï¿½s product. Thatï¿½s why ConvergeNET was originally
created ï¿½ not only to attempt to prove interoperability among vendors
but also to work out the kinks on the way there. In this effort, our sixth
ConvergeNET, which took place at INTERNET TELEPHONYï¿½ Conference &
EXPO from October 4th-5th, showed more progress than ever before, telling
me that we are playoff bound.
On my team for this important game were Agilent Technologies, AltiGen
Communications, Anyuser.Com, Indigo Software, Mitel Networks, Nuera
Communications, Quintum Technologies, and Unidata Communications. From the
bench, we could also call on equipment from 3Com, Cisco, Mediatrix,
PingTel, Polycom, and Siemens. We were ready to play and attempt to defeat
ï¿½non-interoperabilityï¿½ from our field ï¿½ the beautiful Hotel Del
Before running onto the field to take our positions, we had to prepare
ourselves mentally for the game ahead. In effect, NetIQ sang the national
anthem by providing us with the Mean Opinion Score (MOS) for the network.
The score was determined by using NetIQï¿½s new VoIP Manager Suite and the
Call Performance module. NetIQ loaded the software agents onto two laptops
on the show exhibit floor. Then, they configured the agents to emulate
VoIP traffic using the G.711 codec. This showed in real-time that the
network was consistently performing well for VoIP. This score (a good 4.38
out of 5) gave us a basis for comparison for when we were ready to test
the VoIP calls over the network using Agilentï¿½s VQT system.
As the show and therefore the game began, our team got off to a slow
start, but that was partly because the show floor was very crowded, taking
much of our playersï¿½ time. However, a technician from Indigo Software
was dedicated to SIP interoperability right from the start (and I
personally thank Indigo for the commitment), so non-interoperability did
not obtain too much of a lead. Throughout the day, configurations were
being made and displayed on a large screen located above what was
designated as the ConvergeNET portion of Indigoï¿½s booth. It was this
screen that drew some attention from passing attendees, and we often found
ourselves explaining what we were doing to those who asked.
ConvergeNET has always been about awareness, not just for engineers but
also for the consumer. We want everyone to know about the improvements
being made in the quality of VoIP calls and show that different companiesï¿½
equipment are becoming more and more interoperable. At this show, there
was more attendee awareness than in the past, and we will always strive
for continued awareness ï¿½ part of the reason Iï¿½m writing this article.
In the ConvergeNET area, Indigoï¿½s technician configured their SIP
proxy server and user agent as well as SIP IP phones and other VoIP
products from 3Com, Cisco, Mediatrix, Pingtel, and Siemens with the help
from Nuera, Mitel, and TMC Labs. The representatives from Nuera also got
their own gateway configured, and Mitel offered their IP phone into the
mix. By the end of the first day (October 4th), calls from most of these
products were ready to be made. We were cutting into non-interoperabilityï¿½s
Meanwhile, also by the end of the day, the configurations for the H.323
users on our team were in play. Anyuser.Com had their IP phones at bat and
their gatekeeper from their home office waiting on deck. AltiGen had their
gatekeeper and IP Phones (OEMed from Polycom) ready. Quintum had their
gateway portion of the Tenor switch ready to register with the other
gatekeepers and their gatekeeper portion waiting as a relief pitcher in
case needed. Unidata waited in the wings with their IP phone. The stage
was set for a comeback in the second half of the game, which took place
the following day (October 5th).
In the bottom of the sixth inning, Nuera singled, Mitel bunted Nuera
over to second, and Indigo singled Nuera home: All three companies were
able to make calls to each other on the beginning of the second day. For
example, Nuera made a call through Indigoï¿½s SIP proxy to Mitelï¿½s IP
phone. Shortly afterwards, we further closed the gap by successfully
connecting with 3Com, Cisco, and Siemenï¿½s SIP phones. As a matter of
fact, we made calls using every scenario possible with these companiesï¿½
equipment. We even were able to call one phone to another, place that call
on hold, and then dial out and connect to a different SIP phone. For
example, we called from Nueraï¿½s gateway to 3Comï¿½s phone through Indigoï¿½s
proxy and then flash hooked so that we could dial out to Ciscoï¿½s phone.
This was as close as we got to conferencing calls among all different
vendors, but it is a significant achievement nonetheless.
Late in the game, we did also try to configure Mediatrix equipment and
the Pingtel IP phone. Unfortunately, we were unable to successfully
configure the Mediatrix gateway before the show ended and could not
contact Pingtel in time to discover a password we needed to reconfigure
the unit. However, most of the other SIP equipment we used has proven
interoperability with the Pingtel phone already. Also, TMC Labs is
planning to obtain Mediatrixï¿½s IP Communication Server and 1104 products
and put them through the ringer in an upcoming issue of Internet
Telephonyï¿½ magazine. We expect the equipment to perform admirably, but
will let you know if it doesnï¿½t.
I personally listened and spoke on many of the calls that took place,
and most were of good quality, as if we were using the PSTN. On some calls
made involving the Mitel IP phone, the conversation was more jittery as if
muffled like talking on a wireless phone, but that was more noticeable
because of the high quality of other VoIP calls, which easily surpassed
that of most wireless calls. We would prove the high sound quality later
when Agilent brought their VQT into the game.
Maybe Iï¿½m a little bit more hesitant about wireless connections, but
that didnï¿½t stop Quintum from hopping off AnyUser.Comï¿½s H.323
gatekeeper and placing a call to both a regular analog phone and a
wireless phoneï¿½ and I must say, the quality wasnï¿½t bad. AnyUser.Com
also called with their IP phone through AltiGenï¿½s gatekeeper. Unidata
also registered with all of the gatekeepers (AltiGenï¿½s, Anyuser.Comï¿½s,
and Quintumï¿½s) and connected to various endpoints, whether it was
through the gateway from Quintum or the IP phones. While all of these
companies did interoperate with each other, they were unable to
communicate from gatekeeper to gatekeeper before the show ended. However,
true to the commitment to ConvergeNET, these companies plan to continue to
attempt interoperability between each other, including
gatekeeper-to-gatekeeper and other demonstrations.
It was the bottom of the ninth with two outs. With a tie score, but
extra innings loom. Nuera is on third, and Agilent comes to the plate.
Agilent is there to test as many of the IP calls as possible in the
limited time we had left of the show. We decided to test calls from and to
Nueraï¿½s gateway, which had an analog connection so gave us a truer
measure of delay, PSQM, and PAMS scores, to and from 3Com, Cisco, Mitel,
and Siemens SIP phones.
The biggest discrepancies were in the PSQM scores. We did attempt to
test Ciscoï¿½s IP phone for PSQM scores, but were unable to obtain a
reliable score, mainly because of how the phone sat. A ground loop
occurred when testing the phone, causing inconsistencies in the results.
This is a known issue with testing Ciscoï¿½s IP phone with Agilentï¿½s VQT.
In addition, we found mechanical clicks when testing from Nueraï¿½s
gateway to Mitelï¿½s SIP phone, causing the mediocre 2.53 PSQM score.
Without the clicks (which may not be the fault of either the SIP phone or
the gateway), that score would have been much lower. I also want to point
out that these tests are not based on the same measures as done in past
Agilent testing (such as with the Agilent review in the May issue of
Internet Telephony). For example, 3Comï¿½s excellent scores would be more
than a point higher using the older flat-rate measurement, which is still
actually very good when using that rate anyway.
For variation, we measured for PAMS instead of PSQM scores when testing
Siemens IP phone. When connecting from Nueraï¿½s gateway to Siemens IP
phone, the scores indicated some dynamic delay and packet loss, although
the quality of the calls was still clear when actually listening in on the
calls. We feel that the delay during these calls was due to a big jitter
buffer or possibly a slow processor within Siemenï¿½s phone.
Due in part to the reasons detailed earlier, 3Comï¿½s SIP phone tested
most accurately and seemed to have the best overall performance among IP
phones analyzed. Unfortunately, however, 3Comï¿½s SIP phone has recently
been discontinued. We were flabbergasted about that because of its overall
good performance. Also notable is the MOS score, which measured over 4 for
most runs. These are
admirable scores and are significant when comparing the network MOS score
of 4.38, thereby showing consistently high quality calls.
With all of these tests in tow, there is no surprise to report that
Agilent delivered the game-winning hit, ending the sixth ConvergeNET
triumphantly. But while helpful, this game does not enter us into the
playoffs. We have a while yet to go, but I foresee winning more games to
reach our goal. I already envision more interoperability just because of
SIPï¿½s inclusion in Windows Messenger. Whatever one might say about
Microsoft, anyone would agree about how this helps the interoperability
cause. We are also beginning to see products that work or translate
between both H.323 and SIP, helping our cause as well.
And now I shall make a proclamation ï¿½ with continued effort, the
Internet telephony industry will solve major interoperability issues by
the end of 2003. By the time this article is in print, the baseball
playoffs will be long over, but for us, the playoffs are still on the way,
and during that time, we will continue to champion the case of complete
Adam Altman is a TMCLabs editor and the organizer for ConvergeNET at
Internet Telephony Conference and EXPOï¿½.
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