Lab pulls off a testing triple-play
The University of New Hampshire's Interoperability Laboratory (UNH-IOL), with the help of several vendors, recently finished an ambitious test of "triple-play" (voice, video, and data) services
By Jeff Berman, News Editor -- EDN, March 31, 2005
The University of New Hampshire's Interoperability Laboratory (UNH-IOL), with the help of several vendors, recently finished an ambitious test of "triple-play" (voice, video, and data) services, which allowed testers and vendors to see how specific technologies and applications interacted.
The week-long test, conducted from March 21 through 27, examined the performance of triple-play services across a network combining both wired and wireless technologies. The test mimicked the mixed-traffic characteristics of larger companies that are beginning to deploy VoIP (voice over Internet Protocol) and wireless technologies.
Two accomplishments cited by the lab provide a sense of the scale of the endeavor: The test network carried 1.2 terabytes of voice calls over one 17-hour period, and the test included a sustained call rate of 12,000 simultaneous calls.
The session marked the first time that UNH-IOL's three testing groups—bridging, wireless, and VoX (voice over everything)—took part in the same testing initiative.
"Everyone has been trying to do this individually, but we wanted to throw it all together at the same time and see what happens," said Gerard Goubert, manager of the UNH-IOL wireless and VoX consortiums. "We were interested in learning what wired networks do to VoIP technologies and what types of things could tie it up."
The lab is holding back on divulging too much in advance of a white paper it will publish shortly, but Goubert did share that the participants expected some of the results in advance. For example, network bridging loops quickly maxed out their bandwidth constraints, which resulted in VoIP handsets losing their connections.
The test provided a valuable chance for engineers to witness about the "inter-working" issues that can develop among different protocols and layers within different technologies, Goubert said.
Elements and technologies scrutinized during the test included VoIP-over-wireless equipment, hardware and software voice clients, SIP (session initiation protocol) proxies, PDAs, bridging protocols, call generation/termination, voice quality, routers, multiple access points, laptops, streaming-media servers, and a mix of security protocols. Participating companies included Aruba, Azimuth, Cisco, ClearSight, Dell, Empirix, Fluke Networks, IBM, Ixia, Sifos, Spirent Communications, and Veriwave.
The lab welcomes more participants, Goubert said. UNH-IOL can accommodate up to 63 testing vendors with four engineers each. The lab expects to repeat this type of testing at least three times a year, and will increase that to four or five times if the industry's interest merits it, Goubert said.
