Communications Technology: Archive

SuperComm Highlights IP Telephony
Its Not Just For Telcos Anymore
By Justin J. Junkus

Did you attend SuperComm this year? Im willing to bet most of you out there didnt. After all, this years show was held smack dab in between Cable-Tec Expo and Cable 99. Perhaps more importantly, though, its not a cable show. Or is it?

As our industry shifts toward multiple service bundling, of which telephony promises to play a lead role, SuperComm should jump up a couple places on your annual trade show priority list.

The shows "super" moniker is most appropriate for a trade exposition where more than 750 vendors exhibit telephony products on more than 400,000 square feet of show floor, and where five major conferences are held simultaneously with the show.

This years floor was divided into six zones, representing products for wireless and satellite communications, enterprise communications, information technology (IT), components and fiber optics, Internet protocol (IP) telephony, and global service providers.

As a person with a vested interest in cable telephony, I gravitated toward the conference sessions on IP telephony and the related products in the IP telephony zone of the show floor. I also spent some time reviewing the range of digital subscriber line (DSL) products, which provide the enabling technology for IP telephony applications on the telephone companys twisted-pair lines.

These areas of the show delivered two key messages. First, IP telephony is a current, not future, technology that includes more applications than voice over IP (VoIP). Second, vendors are positioning DSL with cables competition as a technology with more uses than high-speed data access.

The conference session delivered by 3Coms director of product line management for Internet telephony, Houman Modarres, provided a listing of IP telephony applications that covered most of the vendor offerings on the show floor. New revenue from these applications, rather than the ability to deliver basic plain old telephone service (POTS), is the motivation for IP telephony technology implementations in telephone company networks.

Per Modarres, "Voice is just the tip of the iceberg." His list included early applications such as "transparent" network trunking, international facsimile, Web commerce, 800 number gateway, Class 4 and Class 5 circuit switch replacement, virtual private line (VPL) service for business, and universal messaging.

Beyond these initial applications, he also listed several enhanced services, such as "follow-me" intelligent call transfer, mobility management, location tracking, call filtering and programmed alerting/response, self-service Web-based subscriber line provisioning, multimedia multicast, and end device advertisement of capabilities.

The common thread to many of these applications is that voice or data information, once converted to packet form and transported using IP, can be accessed and combined with information from other sources that adhere to the same protocol.

Universal messaging services are a good example of such an IP telephony-enabled application that traditional carriers are rapidly adding to their service portfolios. These services allow a subscriber to pick up or send both e-mail and voice mail messages using any available communications device. With this capability, for example, a business traveler can use a cellular phone to access e-mail as a text to voice converted message.

The availability of IP telephony standards and interoperability between those standards is key to rapid growth of applications as subscriber offerings. There are several standards bodies, including CableLabs, the International Telecommunications Union, and the Internet Engineering Task Force, attempting to define IP telephony.

CableLabs has included the IP telephony media gateway control protocol (MGCP) in its Network-based Call Signaling (NCS) 1.0 specification for PacketCable. Similarly, the ITU has defined H.323 to include IP telephony as part of a multimedia specification for local area networks (LANs). The IETF is another standards organization whose concerns include defining IP telephony call signaling.

In a SuperComm session on signaling control of next generation IP/PSTN (public switched telephone networks), Lucents Louise Spergel described some of the relationships in the standards "alphabet soup." Spergel says IP telephony has three layers: services, signaling and media.

H.323 is one of the standards that applies to the call signaling layer. Simple gateway control protocol (SGCP), Internet protocol device control (IPDC), MGCP, and media device control protocol (MDCP) are vendor contributions to a new ITU and IETF standard, which will be known as H.gcp/ MEGACO (media gateway control), that applies to both the signaling and media layers. Yet another effort is under way by an IETF working group called SIGTRAN to define the signaling interfaces between IP telephony and Signaling System 7 (SS7), including how IP will carry SS7s integrated services digital network user part (ISUP) call signaling protocol.

The SuperComm show floor was rich with IP telephony vendor demonstrations that complied with one or more of the standards. Some of the products, such as NetSpeaks Call Agent 1.1 and Telcordias call agent software came close to conformance with emerging PacketCable specifications.

Demonstrations of these products completed IP telephony calls using the SGCP protocol, which is similar to CableLabs NCS 1.0 specification of MGCP. Like PacketCable, however, these products are in early stages of implementation. Most of the vendors with early products close to NCS 1.0 specifications indicated their flexibility to develop and offer PacketCable-compliant products when market demand justifies an offering.

Other vendors showed product lines based upon the more-established ITU H.323 standard for IP telephony. VocalTecs approach to IP telephony standards is typical of the H.323-compliant vendors that have been delivering IP telephony products for field implementation for several years. When I asked VocalTecs Jo Lee about the companys plans for conforming to emerging standards, she replied that VocalTec is focusing on the traditional service providers, using H.323 as the basis for its products.

VocalTecs emphasis is definitely on selling hardware solutions that support revenue-generating applications beyond voice telephony. VocalTec Surf and Call Center is an example. This is a customer service application that implements a simultaneous VoIP telephony connection and collaborative Web browsing session between a firms service rep and its customer. Service providers can package and brand label the solution for offerings to their business subscribers.

A discussion of IP telephony products at SuperComm would be incomplete without mention of switch vendors.

Both Nortel Networks and Lucent Technologies showcased new solutions.Nortel announced 11 new products targeted at customers with enterprise data networks who will be using those networks to provide IP telephony services. The products are based upon the companys open-standards Internet Communications Architecture (Inca). Inca-based systems will be built on a policy-based network infrastructure and on an industry standard Windows NT server.

Nortels Accelar routing switch is an integral part of the architecture. Both standard analog and Internet telephones will be supported. Availability is on a phased basis, with most of the products planned for initial shipment near the beginning of 2000.

The Lucent exhibit included its 7R/E Call Feature Server, which it announced in April for shipment in this years fourth quarter. The 7R/E is an evolution of the 5ESS circuit switch to the packet environment. Lucent is stating that all 3,000-plus features of the 5ESS switch will be available on the 7R/E, including popular features such as call waiting, call forwarding, call conferencing and call transfer. To facilitate the evolution from circuit-switched technology to packet switching, many of the hardware and software components of the 5ESS switch can be re-used in the 7R/E architecture.

As for DSL technology, vendors concurred that a telephone company strategy based strictly upon high-speed data is at best shortsighted because of the highly competitive nature of the data access market. The predominant alternative application is to use the expanded bandwidth provided by DSL to offer multiplexed digital lines over a single twisted pair.

While multiplexing can be an attractive way for an incumbent local exchange service provider to save the costs of additional copper pairs, it also is a good way for a competitive local exchange carrier (CLEC) to enter the market. By serving several lines on one copper pair leased from the incumbent LEC, the CLEC greatly improves its profitability.

The target for multiplexed lines over DSL is predominantly the upscale residence and small business market. The reason for targeting this market as stated by one vendor of the technology should merit some thought by cables strategic planners. According to Jennifer Stagnaro of CopperCom, this market is the source of 40-60 percent of LEC profits.

Physically, the DSL interface at the subscriber location is very similar to a network interface unit (NIU), with one DSL line facing the network and multiple voice ports toward the subscriber. At the telephone companys central office, the DSL lines are connected to a DSL access multiplexer (DSLAM). There are several variations of DSL, but vendors are fast learning to work with each other via open interfaces. SuperComm included an interoperability showcase, where more than 30 vendors demonstrated interoperability of products such as DSLAMs and DSL modems based on the G.lite asymmetrical DSL (ADSL) specification.

Bottom Line

SuperComm: Not Just for Telcos Any More

Even though the SuperComm show is traditionally a telco venue, we need to check it out as well. As cable moves into telephony and other offerings using Internet protocol (IP) technology, this show will take on more significance for us.

The show featured something for everyone, with 750 vendors exhibiting products in six key telecom areas: wireless and satellite communications, enterprise communications, information technology (IT), components and fiber optics, global service providers, and, of the greatest interest to us, IP telephony.

The show delivered two key messages for cable. First, IP telephony is a current, not future, technology that includes more applications than voice over IP (VoIP). Second, vendors are pitching subscriber line (DSL) technology to telcos as a technology with more uses than high-speed data access.

Justin Junkus is president of KnowledgeLink, a consulting and training firm specializing in the cable telecommunications industry. To discuss IP telephony further, or to find out more about KnowledgeLink, you may e-mail him at .