Ready for prime time

<@VM>RFP Checklist: VOIP

Michael J. Bechetti

Moving into the mainstream, VOIP transforms telecom

Voice over IP, the technology that uses Internet Protocol to transmit telephone calls over data networks instead of over the public switched telephone network, may be ready for enterprisewide deployments.

Having largely overcome the notoriously funky sound quality and unreliability of its early years, VOIP now has a place in the telecommunications plans of nearly every federal agency. As a result, integrators need to know what customers are looking for when they seek out VOIP networks.

The Defense Department is an early adopter of VOIP technology, pressing it into service for quick-and-dirty phone networks in military theaters, administrative call centers, even headsets that let fighter pilots on anti-terror reconnaissance dial directly into the Centers for Disease Control and Prevention.

Other federal departments, including the Environmental Protection Agency, as well as numerous state and local agencies, have recognized that VOIP and related IP telephony tools are an economical way to connect thousands of users, including onsite staff, telecommuters and constituents.

When answering government requests for proposals, integrators should draw from current deployments while keeping abreast of the developments that have made VOIP a viable tool. Concerns over the still-nascent technology may linger, but a carefully designed proposal will go a long way toward underscoring the benefits of your planned VOIP architecture, and illustrating how today's technology can minimize an agency's risk.

Assurance and reliability

VOIP has made inroads in consumer and commercial markets, but, not surprisingly, security and reliability issues have made government agencies reluctant to inject the new technology into their tried-and-true phone systems ? technology that runs on mission-critical data networks in which they have a heavy investment.

Depending on the agency's mission, that concern may be more or less pronounced.

Military hospitals, for example "are not comfortable enough with the new technology to put people's lives on the line," said Jim Hill, federal systems engineer at Nortel Government Solutions Inc., Fairfax, Va.

That's understandable. Few people claim, even now, that VOIP is ready to supercede the public switched telephone network. Bruce Fleming, chief technology officer of Verizon Federal Network Systems LLC, Arlington, Va., said VOIP is not "a direct-drop replacement" for a public switched telephone network.

When starting out, Fleming said, an agency should target VOIP for routine administrative traffic: "anything that's nonessential, noncritical, and nonproprietary," he said. From there, agencies and their integrators can grow the platform.

Legacy, private-branch exchange hardware and a motley mix of fax machines, phones, modems and conferencing equipment can complicate finding the best place for VOIP in a telecom system. Integrators need to study what's in place before committing to a project.

Most VOIP vendors cater to mixed environments with IP-based PBX appliances and servers ? the gateways tying legacy devices to the VOIP routers and switches that anchor the network backbone.

But support for old hardware may not live up to the product hype. Experts said there isn't yet a wealth of real-world knowledge on running the legacy side of these new gateways, so contractors should ensure that vendors demonstrate their products' integration abilities, either in real-world deployments or lab settings.
Another concern is the way some firewalls handle voice traffic.

"Voice over IP traffic does not flow through a firewall without an application-layer gateway being present," said Todd Lattanzi, product manager for Adtran Inc., Huntsville, Ala.

This means that a VOIP deployment requires a detailed migration strategy that focuses on hardware and software for easing the transition between legacy private-branch exchanges and IP telephony. It needs to make both work together and ultimately set up an agency for future rollouts.

"We have seen a lot of customers that are migrating their current platform to give them the ability to swap out," said David Ensor, federal sales vice president for Avaya Inc., Basking Ridge, N.J.

Nortel's Hill said the question now is whether you put in an IP soft-switch capability or hardware. Soft switches, which are PCs running software designed to broker call control between older, circuit-switched networks and the packet switching of VOIP, have trouble with number portability, especially in networks that follow the older but better-established time division multiplexing standard for voice data streams.

IP soft switches may work better in installations that start from scratch. Because some time-division multiplexing features don't translate directly into IP private-branch exchanges, Hill suggested upgrading switches to support both standards.

No one's watching

The good news may be, for now, VOIP largely has escaped the budget scrutiny of the Office of Management and Budget Exhibit 300 process.

"The telecom folks have not gotten the charge," Ensor said. He considers telecom budgets a sacred cow in agencies, he said, but added that as voice increasingly becomes viewed as an IT service, that could change. "It forces telecom to talk return on investment," he said.

Start talking return on investment to agencies, and you may have a better chance of long-term VOIP engagement. The business case for VOIP could comprise several factors, including applications of the technology, emerging standards and attention to service levels.

Communications survivability, a hot topic in the wake of recent natural and manmade disasters, is both a potential shortcoming and a strength of VOIP. A poorly executed VOIP network, lacking redundancy and alternate routing strategies, could be more vulnerable than established systems. But VOIP also could function as a backup for conventional PSTN.

"IP telephony will allow the telephones to find an alternative route to the alternate data center," said Hank Lambert, director of business development for Cisco Systems Inc., San Jose, Calif.

Several experts also point to IP trunking as a way to exploit VOIP technologies for short-term gains. IP trunking lets enterprises tie together geographically dispersed sites over a single, IP link, rather than going through expensive gateways to the public switched telephone network.

In the near future, an emerging VOIP standard will make the technology more than just a phone system. And when agencies can heap additional capabilities onto a business system, it becomes easier to justify the cost.

Session Initiation Protocol (SIP), a method of initiating, modifying and terminating multimedia sessions, quickly has become the standard for VOIP communications. It is gradually replacing H.323, the incumbent standard that still enjoys widespread support in many platforms.

SIP features already are helping transform VOIP into a unified, multimedia messaging system that can include videoconferencing, instant messaging and whiteboarding. SIP is critical to these types of communications, because it includes what is commonly referred to as presence detection technology. This is a feature that knows when people are willing and able to communicate. It has its humble beginnings in instant-messaging systems, where it takes the form of the familiar buddy list.

In a VOIP system, SIP and its presence technology can make workers more productive by eliminating phone tag. A VOIP user will always know when someone is available to receive a call.

Feel the presence

The most significant impact of presence technology may be felt in contact centers, where efficiency models depend on when agents are free to take calls.

There is not yet an industry-standard SIP ? groups are still working on a specification ? because leaders with de facto standards, such as Cisco Systems Inc. and Microsoft Corp., guard the value of presence technology in their product strategies, Ensor said. Be sure any VOIP proposal fully explores SIP possibilities and compatibilities to ensure a customer can get the most from its VOIP system.

Finally, any business case for VOIP would be undermined dramatically if it couldn't guarantee an acceptable service level. Nortel's Hill said that when formulating proposals, integrators need to pay attention to quality-of-service techniques and not just throw bandwidth at VOIP systems to ensure they work properly.

The latter approach is one Hill has seen at several large agencies, including the Defense Department. "At some point, they're going to have to stop doing that," he said.

One reassuring quality-of-service technology, he said, is differentiated services, commonly known as Diffserv, a method for classifying large-network traffic and using service-level agreements to guarantee the volume and speed of each class of communication. Another tool Hill recommends is Power over Ethernet, which keeps electricity flowing to VOIP equipment that normally isn't powered like conventional phone lines.

So where does an integrator building a VOIP system look for government-grade products? Today, the closest thing to a clearinghouse is the Defense Department. Its Joint Interoperability and Test Command runs a certification program that ensures VOIP products meet interoperability, performance and security minimums prescribed in two standards: PBX1 and PBX2.

The stricter PBX1 standard approves VOIP equipment for command and control systems. It includes testing for multilevel precedence and pre-emption, which lets high-priority users break through voice traffic during emergencies, an important consideration when building a VOIP infrastructure.

Other agencies are free to adopt these strict standards, but they aren't required. Not everyone says what's good for the Defense Department is good for us, too, Ensor said.

David Essex is a freelance technology writer in Antrim, N.H.
Attention to detail will ensure an integrator's success in writing a voice over IP request for proposal, industry analysts and experts said. Many VOIP guidelines are detailed in the Defense Department's "Voice Networks Generic Switching Requirements," published by the Defense Information Systems Agency. Check it out at and type 183 in the Quickfind box. Here are some tips as well:

  • Address quality-of-service expectations, including different service levels such as priority or critical, for certain classes of users. You can ensure adequate quality of service by insisting that vendor partners describe their hardware's quality-monitoring features, such as a "blame feature" that helps assign responsibility for failures. Quality-monitoring features typically measure network traffic indicators, such as
    jitter, buffer sizes and latency.

  • Make sure there are alternative transmission paths that add redundancy and allow subsecond failover. Without these, your customer might be without phone service in the event of a disaster or other emergency.

  • Continuity-of-operations planning requires alternate sites with phone and data systems that employees can use almost like their own. VOIP requires data rollover from headquarters to the alternative site; be prepared to detail how you'll handle this.

  • Work with vendors to demonstrate that their equipment interoperates with other vendors' hardware at both the data (layer 2) and network (layer 3) levels.

  • Ensure VOIP products are Session Initiation Protocol-compliant, not just SIP-enabled. Some vendors offer only partial implementation of the new standard, relying more on the older H.323 standard.
  • Be prepared to launch a VOIP pilot program. Agencies may use it to gauge the grasp of their
    legacy infrastructure and possibly reveal holes in the solution or quality-of-service problems such as delays on the data network.

  • Include power over Ethernet. It avoids expensive dedicated wiring. Most products have power over Ethernet, but a few older models do not. Look to solutions that have the IEEE standard for power over Ethernet (802.3af) coming out of the wiring closet from an "end span" switch, the best setup for powering new devices as the network expands.

  • Make sure your proposal includes a backup, uninterruptible power supply that can keep all phones
    running for at least the Defense Department standard of two hours.

  • Ask vendor partners if their products are fully Section 508-compliant, not just 508-capable. Section 508, the federal law requiring information systems to be accessible to the disabled, applies to VOIP.

  • Offer detailed licensing information that spells out how much the customer will pay for phones, servers, data ports and software, now and in the future. Some vendors have been known to triple their license fees in a single year.

Reader Comments

Please post your comments here. Comments are moderated, so they may not appear immediately after submitting. We will not post comments that we consider abusive or off-topic.

Please type the letters/numbers you see above.

What is your e-mail address?

My e-mail address is:

Do you have a password?

Forgot your password? Click here

Washington Technology Daily

Sign up for our newsletter.

Terms and Privacy Policy consent

I agree to this site's Privacy Policy.


contracts DB