Assessing VOIPs Role

Avaya, Nortel Systems make an increasingly strong case for IP-based enterprise telephony.

eWeek Labs recently got an earful of voice over IP. Working with VOIP equipment from industry leaders Avaya Inc. and Nortel Networks Ltd., we discerned the strategic decisions IT managers can make now that will enable them to successfully bring VOIP to the enterprise and improve data network performance at the same time.

Putting voice traffic on a data network can significantly lower capital costs by unifying cable plant and network equipment. It can also lower operational costs with distributed call center agents and the enabling of self-administered conference calling and toll-bypass outside the United States.

IT managers who converge data and telecommunications traffic—and likewise merge the IT and telecom departments—will likely reap the rewards of significantly lower add/move costs associated with telephone handsets, staff efficiency gains, easier deployment of new calling features and increased network reliability for data applications.

However, VOIP is also fraught with barriers, and one of the biggest is the legendary reliability and quality of current phone systems. Add to that rock-bottom tariffs for domestic calling, the lack of a VOIP-only "killer app" and—most significant of all—the cost to upgrade data networks to carry voice traffic, and most organizations can find little reason to immediately switch.

However, whats new now is the availability of advanced VOIP applications, which will be the telephony growth platform of the future. This means everyone from station users (telecom parlance for a user of a telephone handset), to call center agents, to executives and their assistants to reception operators and telecom managers can use VOIP equipment today with the same features they get from the current phone system.

During testing of Avayas and Nortels telephony equipment, Category 5 data cabling provided dial tone and power for handsets. Call quality using both vendors systems was, for the most part, indistinguishable from standard digital telephones.

To get to this point, however, most data networks will have to undergo substantial remediation—both in terms of adding equipment to supply power over Ethernet and implementing protocols in switches and routers. For example, both Avaya and Nortel use the IEEE 802.1p protocol (which defines how multicasts should be filtered at Layer 2 to ensure that they are not propagated over Layer 2-switched networks) and 802.1Q (for virtual LAN tagging).

To evaluate not only VOIP products and infrastructure but also the process organizations must go through to determine the technologys return on investment, eWeek Labs developed an RFP (request for proposal) for a fictitious company called Industry Inc.

We worked with Avaya and Nortel to fine-tune the RFP, which detailed a two-phase voice implementation (see chart).

The first phase, a large pilot project, required that the vendor support 1,500 VOIP handsets with equipment available today. The second phase specified supplying 10,000 VOIP handsets—enough to outfit the entire Industry user base—with technology available today and/or slated for release within the next year. The ballpark cost estimates, assuming numerous variables, are $2 million for Phase 1 and $7.9 million for Phase 2.

Our requirements were guided by the principle that the VOIP implementation must provide service equal to or greater than the phone system its replacing. For example, handsets must deliver dial tone even in a power outage, and audio quality must equal that of a traditional business telephone. Furthermore, management features used by telecom staff to maintain the system must meet or exceed those already available. (For more VOIP requirements, see chart.)

In terms of network security, one big advantage that traditional telephone systems have over VOIP is that each station is wired directly back to the PBX. With that said, the phone systems we evaluated took security very seriously and are on firm footing to secure the system from attacks and abuse. However, as VOIP systems become more widely deployed, weaknesses will be found. IT managers will have to be particularly vigilant about the performance and security of voice applications in the enterprise.