Satisfying An Urge To Converge
BY ADAM ALTMAN
Commitment. Communication. Constitution. Convergence. These are the four
"C" words that should be the focus for VoIP interoperability.
Everyone must commit to the effort of interoperating with each and every
piece of equipment in the Internet telephony industry. Everyone must
communicate with each other about all of the issues surrounding
interoperability. Everyone must help constitute standards: Standards that
will go a long way towards enabling an infrastructure as reliable -- and
with equal or better sound quality -- as the PSTN. In this way, everyone
will converge, and a new age in communications will materialize as a result.
Unfortunately, the Internet telephony industry is a ways off from
completely interoperating, but TMC Labs has committed to helping this
happen. That's why ConvergeNET, a proving ground for interoperability, was
created. It is also why we have reported and will continually report
honestly about the events that took place at ConvergeNET. That's the only
way to ensure progress and eventually attain our goal.
Telling It Like It Is
Our fourth installment of ConvergeNET, which took place at the INTERNET
TELEPHONY Conference & EXPO in San Diego from October 5-ï¿½6,
attempted to bring together more than 25 companies for interoperability
demonstrations on the show floor. While we had success with many of these
demonstrations, we were not without our share of disappointments as well. As
readers know, TMC Labs has no qualms about telling it "like it
is." If we see a product that claims to interoperate but cannot prove
that it does, then it's our job as journalists to report that news. A
perfect example of this is AG Communication Systems/Lucent Technologies, who
claimed to interoperate in their labs with other vendors, but could not
prove their interoperability with the six or so vendors in their pavilion at
INTERNET TELEPHONY Conference & EXPO. While we harbor no misgivings that
they have in fact successfully interoperated in their labs, there remains a
need to test interoperability within a real-world scenario (as opposed to a
lab environment). We challenge AG Communication Systems/Lucent Technologies
to solve whatever technical issues they had so that they can successfully
prove interoperability at our next installment of ConvergeNET at INTERNET
TELEPHONY Conference & EXPO in Miami, February 7ï¿½9, 2001.
We must also remember that attempting a demonstration and failing may be
more beneficial for interoperability than successes are. Indeed, we all
learn from failures, and through them we might get closer to our goals.
However, failure to even attempt a demonstration achieves nothing...
And Now, The Good News...
Now that I've said that, I can focus on some positives. First, I would
like to commend Tundo, one of our sponsors, for continuously coming to the
plate and delivering successful demonstrations at ConvergeNET, for their
input to our ConvergeNET video, and for their efforts to show the
demonstrations to attendees via a special ConvergeNET map of the show floor
illustrating which exhibitors were interoperating. Tundo has been involved
in every installment of ConvergeNET that has taken place thus far and has
lead the way in our interoperability demonstrations. In the latest
ConvergeNET, they were the first to set up their equipment, and then they
converged with Quicknet Technologies, Inc. and ShelCad Communications, two
other companies that have previously and successfully worked together at
ConvergeNET. Quicknet and ShelCad had no problem registering with Tundo's
gatekeeper, and then calling one another using the H.323 protocol. Later
that day, Active Voice also joined in with successful results.
In an effort to create a SIP network, 3Com Corporation, dynamicsoft, Inc.,
Nuera Communications, Pingtel, SS8 Networks, and Ubiquity Software
Corporation attempted to use their equipment to work together. Because of
the high turnout at the INTERNET TELEPHONY CONFERENCE & EXPO and because
it was the first attempt to establish a SIP network at ConvergeNET, these
companies took a while to interoperate. The first success came towards the
end of the first day when dynamicsoft successfully talked with Ubiquity
through their SIP proxy server.
Meanwhile, TelStrat International demonstrated its latest product for
Nortel Networks, the Remote Office 9110. Two Remote Office 9110 telephones
were used at the show, one in TelStrat's booth and one in Plaintree
Wireless' booth. The Remote Office 9110s were set up using the G.729 voice
compression codec. Calls placed to/from these telephones were transported
via the Internet without any voice QoS equipment. Both companies were able
to demonstrate: Calls originating from San Diego to users on a Meridian 1
PBX (IP to digital telephones), calls originating from San Diego to anywhere
in the world (IP to circuit-switched networks), calls between the TelStrat's
booth and the Plaintree's booth (100 percent IP), and inbound calls
terminating at the Remote Office (circuit-switched to IP). While this was
not done using any of the main protocols (they used a proprietary protocol),
TelStrat was inclined to say that they will attempt to use one or more of
these protocols for converging with other exhibitors at our fifth
installment of ConvergeNET in Miami.
The second day of the show brought some more ConvergeNET successes and
challenges. On the H.323 end, NetCentrex and UniData Communication Systems
registered with Tundo's gatekeeper and made successful VoIP calls with the
other registered participants. A number of the companies also registered and
made calls through NetCentrex's gatekeeper. Perhaps more important was the
fact that Tundo and NetCentrex's gatekeepers communicated with each other.
This is the first time that we know of that two gatekeepers from two
different companies converged in a real-time, live setting. If different
gatekeepers interoperate with each other, then the equipment that the
gatekeepers control should also be interoperable. This significance spells
good news for the future of VoIP interoperability.
As for the quality of the VoIP calls, we tested for PSQM scores by
linking Agilent Technologies' Telegra VQT system to the H.323 network. We
made live calls from Quicknet to Tundo and measured the PSQM scores. They
averaged 2.6, which is an acceptable score for VoIP calls, especially since
the tests were performed on the show's shared network in which video,
co-browsing, and other functionality were also using bandwidth on the show
floor. The lower the PSQM score, the better. Above a score of 4, one must
begin to worry about serious packet loss and voice degradation. Latency,
jitter, and echo also did not present a significant problem for any of the
H.323 calls that were demonstrated by any of the successful participants. In
the future, we plan to continue to test the ConvergeNET VoIP calls to prove
not only that the call connects, but also that it goes through as a quality
We also attempted to add Belle Systems' IP billing system onto this H.323
network. They tried to connect to both Tundo and NetCentrex's gatekeeper but
were unsuccessful because of a RADIUS issue. However, now that we know about
the problem, we have hopes to fix it in the near future.
While all of these H.323 demonstrations were taking place, the companies
using SIP were also achieving some more success. 3Com successfully called
Ubiquity and Pingtel from their SIP phones to the subsequent endpoints. To
test the quality of a VoIP call, I personally made a call from Pingtel to
3Com's booth. The call did connect, but had too much static to hear the 3Com
representative clearly. Later, Rich Tehrani, TMC's president, also tried
this same call, and the reception was much better. The static was probably
due to heavy traffic on the show floor at the time of my call.
SS8 also was interworking with Pingtel using SIP. Since SS8 did not use
an end point, we could not actually hear the call, but could see SS8's user
agent connecting with Pingtel's phone. On another note, dynamicsoft made
calls back to themselves through Aravox's firewall, which had the ability to
open and close ports as VoIP packets passed through the firewall.
Consequently, this allowed for VoIP calls to pass through the firewall
without impeding too much on security issues. While this was not necessarily
a ConvergeNET demonstration, it is important to note since it has
implications to the overall success of VoIP interoperability.
As it turns out, with the exception of Nuera, everyone in the SIP network
was using the G.711 compression codec for their calls. Nuera attempted to
use the G.729 codec without success and could not switch over to G.711
before the show ended. However, the effort was there, and we fully expect
Nuera to successfully interoperate at ConvergeNET in the near future. During
this show, G.711 was mostly used for the SIP network and G.723 was used for
the H.323 network. For the next ConvergeNET, we plan to use more codecs
successfully. We also hope to use an H.323 to SIP signaling gateway so that
companies using either protocol can converge with each other. In addition,
video, application sharing, use of other protocols such as MGCP, and other
functionality may be included as part of these demonstrations.
"C" You In Miami
So that's the latest news about ConvergeNET. In the future, it is our
intention to use the four "C" words to continue to educate
attendees while advancing VoIP interoperability. We would like to see
commitment among all companies. We must make sure we communicate our ideas
with each other. As a result, we shall form the constitution to overcome the
obstacles. Then, and only then, we shall all converge. We urge all Internet
telephony companies to participate at the next ConvergeNET -- Consider this
an open invitation to attend the next installment of the world's largest
VoIP interoperability showcase.
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