Users learning to manage VoIP networks

Gary Todd knew that managing a voice-over-IP network involved a lot of preparation. So he and his staff tapped the knowledge of specialists with experience in data and voice communications and chose VoIP products from a vendor with a telecom background. But he still learned something new after implementing the network.

"We noticed we weren't allocating enough bandwidth to the voice applications," says Todd, OmniAmerican's assistant vice president of network services. Todd, along with Jim Evans, the company's vice president of IT, soon discovered they needed to apply quality-of-service (QoS) technologies, such as compression and priority routing, to the voice applications so they would get the bandwidth needed to perform across the data network at the Fort Worth, Texas, credit union.

Implementing QoS is one step network executives can take to help manage and ensure the VoIP network they deployed to save money in remote office connection costs will deliver the return on investment they want.

But users also must manage a number of new network elements, such as media gateways and IP phones, that they previously didn't have. IT staff also will be faced with more traffic to manage on the IP network, and new voice applications could affect overall network performance.

The need to manage VoIP environments is growing: According to a recent report from Cahners In-Stat, corporate adoption of IP telephony is on the rise with the U.S. market for VoIP handsets reaching $1 billion in 2001. The report also found that the market for IP voice gear would reach $5 billion by 2006.

"Voice applications are very demanding. You've got to give them everything they're asking for," Evans says. "Make sure you have enough bandwidth and that the LAN and WAN equipment is sufficient for the voice."

VoIP poses performance challenges perhaps new to some network executives. Because VoIP technology puts voice information into a digital format and sends it as packets across the IP network, packet loss and delay become major flags of performance problems. Jitter also is a problem because it can cause delays or drop packets. Voice requires a steady stream of packets.

Other performance management challenges are call quality and clarity. Call quality is a measure of conversational performance, while call clarity is more about how well the listener can hear. Delay has more of an effect on call quality, or a conversation, than call clarity, or a one-sided call such as voice mail.

Vendor input

Many vendors are looking to address the needs of VoIP users. VoIP equipment vendors such as Avaya, Alcatel, Cisco and Mitel Networks offer software that gives customers a view into application performance. These tools typically rely on reading the VoIP protocols, such as H.323 and the Session Initiation Protocol, to get a handle on how fast traffic traveled the network.

Network management software makers such as NetIQ, NetScout, Integrated Research, Telchemy and Brix Networks sell VoIP-specific products that can manage voice and help customers understand the performance metrics of voice. And to maintain one consolidated view of the network, VoIP software can feed the voice-related data to a network management console such as Hewlett-Packard's OpenView, Tivoli Enterprise Console or Computer Associates Unicenter.

OmniAmerican uses CajunView VoIP management software from Avaya to track bandwidth and call statistics.

"The voice industry has always been about availability. While OK for data at times, [less than 100%] is not acceptable to a voice provider," says John Dinan, telecommunications analyst at the Santa Clara County Office of Education in California.

Dinan has yet to upgrade to VoIP because of the potential for poor call quality. "There are still many quality issues. Even with people using cell phones, users expect high quality on their wired phone."

In terms of QoS, OmniAmerican's IT staff is doing prioritization on the Avaya Cajun data switches, with port-specific prioritization on a few select data ports. Evans adds that latency hasn't been an issue due to the amount of available bandwidth they've provisioned for the voice applications.

Todd and Evans also upgraded servers and switches with Avaya equipment and installed IP phones at remote locations. Specifically, they upgraded the network with voice-enabled phone switches and dedicated IP phone switches. The digital phones at the branches communicate over the WAN to a voice-enabled switch, giving OmniAmerican one unified IP phone system, a centralized voice mail server and four-digit dialing to and from all its locations.

With the VoIP network, OmniAmerican saves about $800 in local voice circuit charges per month at each of the company's 13 remote offices. Todd says the network upgrade lets OmniAmerican save up to 70% in connectivity costs using VoIP.

Management help

Some enterprise users cannot afford the investment required to manage their VoIP networks. Cohen Financial, a real estate investment-banking firm, decided to outsource its VoIP management. John Ahlberg, CIO at the Chicago firm, says the company wanted to be able to dial four digits and reach any of its 10 offices across the country.

"The idea of voice over IP was great, but we wondered, 'Once it's installed, who are going to be the smart people to manage it?'" Ahlberg says. He needed to buy three new PBXs and find the expertise to manage the VoIP in his network, which "just wasn't cost-effective."

The firm decided to enlist the services of NetSolve, a management service provider, to oversee the VoIP network and alert staff at Cohen of network problems.

NetSolve supplies Cohen with the equipment, management tools and technology expertise to manage VoIP, and NetSolve uses a VPN to connect to the firm's network. Ahlberg says using NetSolve made investing in the new technology less expensive because he didn't have to invest in three new PBXs or add to his network staff to manage VoIP.

Cost wasn't the primary concern for Brenda Helminen, but implementing VoIP still saved her from financially supporting two networks. She's upgrading to VoIP to centralize and standardize her voice and data networks. "It's cost prohibitive to run two separate networks," she says.

Helminen, director of telecommunications engineering at Michigan Technological University in Houghton, is in the process of rolling out 3,000 to 4,000 IP phones across campus. Helminen uses local switches and OPS Manager software from Mitel Networks to ensure her phone service stays available She says the 75 IP phones she has up and running use a virtual LAN supported by local switches to traverse the network. The virtual LAN prevents the voice applications from having to compete for bandwidth with the data traffic.

"Phone service is a business service. Most people don't see it as an IT service," Helminen says. "People expect to always have good phone service. I don't want to take any chances in losing service."

RELATED LINKS