July 2000

BY ADAM ALTMAN, TMC LABS

Suppose Alexander Graham Bell and his supporters had not pioneered the telephone. In Bell's day, many believed that the invention would never take off. Why use a strange new contraption when you could just walk to town and talk to anyone you wanted to communicate with? Times have changed since then, and that strange contraption has played a large role in those changes. What would this society be like without the phone?

A similar notion was inevitable with the invention of the computer, especially in the early '80s when computers were beasts that were slower than that proverbial tortoise. More recently, it has been the lethargy of developing standards that has crippled many new technologies. For example, TCP/IP has been around a long time, but it was only in recent years that transmitting data over this protocol became the de facto networking standard.

Now, some Internet telephony companies are contributing further to this evolution by perfecting Voice-over-IP (VoIP) technologies. As Internet telephony companies become more and more advanced (some VoIP applications are even better than analog phone quality), the main issue becomes interoperability, and there is a long road to pioneering a compliance standard that would revolutionize our society once again. While we are still far away from complete interoperability because of competing protocols like H.323, SIP, and MGCP (among others), equipment using proprietary applications, and standards committees battling over which parts of which protocols should be "the standard," there is hope for the near future. Successful demonstrations in interoperability compliance go a long way toward showing that it is an attainable goal, and there was no demonstration more successful than the Spring Communications Solutions EXPO in Washington, D.C. at the end of April. That was the third installment of ConvergeNET, which is dedicated to demonstrating VoIP interoperability from anywhere on the show floor of TMC's Communications Solutions EXPO and Internet Telephony Conference & EXPO.

At TMC Labs, we are very familiar with what can go wrong with specific equipment and software. In a live environment with a short time to achieve interoperability, it is even more critical that successful demonstration runs be made as quickly as possible. TMC Labs is very involved with ConvergeNET, even to the point of helping participating companies and their engineers solve compatibility issues. We believe in VoIP, interoperability, and those pioneering companies willing to subject themselves to possible failure in a real-time environment. Some of the companies involved had never even worked together before the EXPO and were still able to interoperate.

Nine companies were key participants in ConvergeNET, and Tundo sponsored the event. The main participants were Cirilium, Conita Technologies, e-tel Corporation, e-Voice Communications, Inc., iFace.com, Nx Networks, Quicknet Technologies, Inc., ShelCad Communications, Ltd., and Tundo.

Companies actually called from their own EXPO booths to other companies' booths on the show floor. TMC designated one area as the center for ConvergeNET, and Tundo's gatekeeper was located there, as was equipment from Quicknet and Conita. The private ConvergeNET networks, provided by WOMBO, Inc., were centered there as well with drops going to participants' booths. With this network setup in place and after a preliminary meeting on setup day, these companies were ready for the demonstrations to begin.

On the first day of the show, it took a little while to set up the equipment, make sure everyone had the appropriate IP addresses, and tweak some configuration settings, but soon we were off and "VoIPing," using the H.323 protocol. The first modest success was achieved when ShelCad and Cirilium made point-to-point calls from booth to booth. We were visiting ShelCad during this test, so we took the call from Cirilium. Because of the noise on the EXPO floor, it was a little difficult to hear the voice on the other end of the line, but we were able to make out what was being said and did not hear much latency or echo. In addition to ShelCad, Cirilium was able to make point-to-point calls with iFace.com, Conita, and Quicknet using the G.723 and G.729 codecs. Unfortunately, they were never able to register with Tundo's gatekeeper, so they only enjoyed point-to-point VoIP success.

Larger success came after most of our participants registered with Tundo's gatekeeper and were able to make VoIP calls through the gatekeeper to other companies' booths. As a matter of fact, with the exception of Cirilium and e-Voice, all the other companies were able to register, whether the registered equipment consisted of an IP phone, other end points, or a gateway. Nx Networks had limited success -- in part because of the codecs they were using (G.711 and G.729a). Much of our success came when using the G.723 compression codec. However, Nx Networks was able to use Tundo's gatekeeper to connect with e-tel. We listened to one of the calls that e-tel made when it was a little quieter on the show floor, and were amazed by the clarity of the call and the lack of latency and echo.

On both days of the show (along with other demonstrations), Quicknet attempted to communicate with each and every participant, either through Tundo's gatekeeper, via a point-to-point connection, or both. They were largely successful. They were even successful when making a call to a Komodo Fone, as were Tundo, iFace.com, and Cirilium. Furthermore, they attempted to do this using both the Windows and Linux operating systems, headed by Ed Okerson, an authority on Linux. Quicknet was first successful when communicating with iFace.com, and then with Tundo, ShelCad, e-tel, Conita, and Cirilium. Quicknet attempted to communicate with Nx Networks and e-Voice, but with only limited success. There was no audio when Quicknet called Nx Networks, and e-Voice could originate a VoIP point-to-point call, but could not receive one. e-Voice had a problem with a dropped connection after receiving a call, and could not solve the problem in the short time that we had for the demonstrations.

In almost every capacity, the demonstrations were extremely successful, and everyone concerned learned much from the experience. As a matter of fact, because of our success and our own cockiness, we decided to demonstrate a wireless VoIP connection on the show floor. AIRLINX, who provided the wireless equipment, used the CompactLink 20/350 laser system to seamlessly bridge two Ethernet LANs running VoIP traffic. Tundo and Quicknet supplied the VoIP network telephony systems for the demonstration. Through this real-world telephony experiment, we proved that wireless laser communications do allow for transparent physical layer network extensions for time-sensitive VoIP data.

As you can probably tell, we're very excited about what transpired with ConvergeNET at the Spring Communications Solutions EXPO in Washington, D.C., as are many companies in the Internet telephony space. Believe it or not, we're even more excited about the awesome potential for ConvergeNET at the Internet Telephony Conference & EXPO in San Diego on October 46. We plan to continue to work with the companies mentioned as well as many more companies, and we plan to venture into additional aspects of interoperability in the Internet telephony industry. These should include demonstrations with most protocols, and we plan to include more new Internet telephony technologies than have ever been demonstrated in this type of environment. We are even setting up a ConvergeNET Advisory Board so that this can be organized properly.

Everyone involved with the third installment of ConvergeNET should be proud of their achievements. We have made a breakthrough in VoIP interoperability demonstrations, and believe that we will break more new ground at our next event, thereby continuing the evolution of VoIP technology.

Adam Altman is a technology editor for TMC Labs. He also organizes and directs ConvergeNET. He may be reached at aaltman@tmcnet.com.

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