Telecom managers swap VoIP rollout tips

Network outages, bandwidth-squeezing viruses and overheating VoIP gear are among the myriad problems that can hinder an enterprise VoIP rollout, said several IT professionals at the Fall VON 2004 conference this week. But having the right people and a good IT game plan are key to pulling off IP convergence projects with minimal pain.

The VON kicked off on Monday with a telecom managers’ roundtable - “Migrating to the IP PBX” - where a diverse group of IT executives told stories of migrating from traditional voice to IP and IP-enabled PBX environments. If there was a theme among the users who spoke, it was that the benefits and challenges of installing a converged enterprise infrastructure are as varied as the different types of organizations rolling them out.

Among the speakers was Merrill Lynch’s Todd Goodyear, vice president and manager of voice product development, who detailed the strategy for the financial giant’s much-publicized swap-out of Cisco VoIP equipment for a mix of TDM and IP from Avaya.

Merrill Lynch was on the VoIP vanguard when it installed a Cisco-based IP PBX campus in Hopewell, N.J., in 2000, and IP telephony helped the firm overcome drastic relocation issues after 9/11. But it was the onslaught of the SQL Slammer virus two years ago that made the firm rethink its jump into IP. 

E-mail viruses took our data network and crumpled it,” Goodyear says. “That’s when our business took a look at  [IP telephony] and asked, is this really mature?”

That’s also when the firm decided to take a hybrid approach to voice. The firm replaced Cisco VoIP gear with Avaya TDM/IP hybrid equipment in New Jersey and in other locations.

“Going forward, we’ll do a TDM and IP hybrid,” Goodyear says. That led to our decision in 2003 to announce that were moving away from Cisco. It was not because there were problems with our Cisco technology. Our strategy changed from all-IP to hybrid.”

But the hybrid approach will still involve many IP phones. The company will have more than 10,000 devices installed by 2006. In deploying IP endpoints on such a large scale, Goodyear gave some advice.

“All [IP PBX and phone] code has bugs in it, and you’re more likely to find them in the field than in the labs,” Goodyear says. To deal with this, having a staff with deep technical knowledge of the products is key. “It’s a matter of how you react to them and plan to handle them.”

One of the nuts-and-bolts issues Goodyear has encountered in deploying VoIP is dealing with increased power requirements for supporting IP phones on desks.

The IEEE 802.3af standard for power over Ethernet (PoE, used to power IP phones from LAN switch ports) requires 15 watts of power to phones. “For large [PoE] deployments, it’s hard to get that out of a [standard] 2,500-watt [universal] power supply,” Goodyear says.

Users should expect to upgrade electrical services in wiring closets, as well as plan for more cooling, since PoE switches produce more heat than regular LAN gear.

Deploying IP telephony also may require network engineers to re-examine the tools and methods used to monitor network performance. This was the case as at Grant Thornton LLP, a Chicago-based accounting consultancy with offices nationwide. The firm is consolidating its voice network into three data centers nationwide with Avaya S8700 hybrid IP/TDM PBXs, which will support more than 50 offices across the country.

When the firm started on the VoIP path, users experienced problems with dropped or garbled calls due to packet loss, says Kevin Lopez, national manager of telecommunications for Grant Thornton. 

“Our network engineers were only looking at data thresholds for packet loss,” Lopez says. “They were just looking at it from a data point of view. We needed to change our perspective.”

The IT group added specialized IP telephony monitoring tools from Avaya to its network management infrastructure, which is based on HP OpenView. This let the firm see call performance on a more detailed level to diagnose problems.

One issue the IT group is still working on is finding the optimal voice compression codec on which to standardize. While the G.711 (uncompressed at 64K bit/sec) provides the best voice clarity, it sometimes chews up bandwidth when call volume is high on the firm’s network of T-1 links to its branches. The G.729 codec (compressed to 8K bit/sec) eases congestion, but has caused some end users to complain of poor voice quality.

“We’re still trying to find a medium between these two codecs,” Lopez says.

Bandwidth wasn’t the issue at the City of Daytona, Fla., which also moved to centralized, IP-enabled PBXs three years ago to support more than 1,000 city employees in administrative and public service offices.

The centralized, IP-enabled Nortel PBX runs over the city’s SONET-based fiber backbone and helped to eliminate 17 different phone systems across various city departments, according to Grady Meeks, the city’s director of information systems.

The antiquity of the city’s phone system helped sell the city council on the idea of VoIP and convergence, says Meeks.

“We were at the point that if certain [legacy] phone systems we had were to break, we probably wouldn’t have been able to fix them,” he says.

The Nortel-based system also provided the first citywide five-digit dial plan and gave every employee a voicemail box.

Besides the benefits of easier administration and local tie-line costs, the system has also allowed the city to act as a CLEC in the Daytona area, offering some small businesses in the city converged voice and data services. Meeks says this has made the VoIP network a revenue source, bringing in almost $35,000 last year for the city.

Another issue challenging some IP telephony adopters is integrating multi-vendor applications on a converged network. At the University of Utah, IP PBX products from 3Com, Cisco and Avaya are running in different areas, such as the school’s medical research center, main campus and the University of Utah Hospital.

The long-range plan at the university is to move all 16,000 phone lines from Centrex to IP telephony, says William Jahsman, principal with Park City Consulting Group, which is helping in the convergence project. He says IP telephony vendors still need to do a better job integrating their convergence applications with standard-based technologies, such as Lightweight Directory Access Protocol.

“There are a lot of niche products in the market today,” Jahsman says, such as applications that integrate desktop click-to-dial features with e-mail and softphone technology. “If you’re trying to take advantage of those things, you’ll likely be getting a stove-pipe product that doesn’t integrate with your infrastructure, such as LDAP.”

LDAP interoperability will be key for any converged applications being deployed at Utah, Jahsman says, since the directory protocol is used widely for provisioning services on campus.

Join the Network World communities on Facebook and LinkedIn to comment on topics that are top of mind.
Related:

Copyright © 2004 IDG Communications, Inc.

IT Salary Survey 2021: The results are in