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The State of VoIP

It doesn't take hyperacute bat senses to read the signals: Our readers and vendors agree that voice over IP is here to stay. In fact, our recent poll of 553 readers revealed that 39 percent plan to install production-level VoIP within 12 months. Fifteen percent will follow in two years.

Vendors are pumping billions of dollars into VoIP R&D, with intriguing results. Even systems for small and midsize businesses and enterprise branch offices sport features that enhance productivity. Our RFP for a 200-user office garnered eight vendor proposals touting flexible, money-saving telecommuting and teleconferencing options, along with efficiency boosters like unified messaging and presence (see "VoIP to the Rescue,").

Keen competition among proven vendors, coupled with a cadre of small, nimble players, gives VoIP buyers plenty of options. Depending on how you slice the market, either Avaya or Nortel, which dominate in legacy PBX installations, lead in VoIP. Synergy Research Group says Avaya shipped the most VoIP ports globally in Q4 2003, while Dell'Oro Group's market share numbers

for Q4 2003 put Nortel in the lead. Hot on their trail are Alcatel and Siemens, which lead the field in Europe and are aggressive on this side of the pond.

Not surprisingly, vendors are reporting increasing VoIP port sales versus legacy TDM (Time Division Multiplexing). But don't declare TDM dead yet. Even though VoIP is the future, only 20 percent of our poll respondents said TDM phones comprise 5 percent or fewer endpoints.

Choices, Choices

Beyond balancing pure VoIP and TDM hybrids, IT has another strategic decision to make, between vendors that consider VoIP an application, independent of the network data infrastructure, and those that sell the data network infrastructure as part of the overall package. In one camp, Alcatel, Cisco Systems and Nortel push their data-networking products as part of the VoIP system. Avaya, Mitel Networks and Siemens emphasize their products' ability to run on heterogeneous network infrastructures and may even partner with network-equipment vendors like Enterasys Networks, Extreme Networks, Foundry Networks and Hewlett-Packard.

There are benefits to sticking with one vendor, but before buying into a proprietary system, weigh the trade-offs. Your legacy PBX doesn't require a single data-infrastructure vendor, and neither do the business applications that run on your network. Why should VoIP be any different?

Beyond proprietary feature sets, there are other ways to get locked into one vendor. For example, many enterprise phone systems require the phones and the switch to come from the same source. This is nothing new--PBX vendors have always insisted that you buy high-end digital sets from them. For simple, single-line phones, though, there was always the option of getting an inexpensive analog device that works on any vendor's PBX.

Despite the fact that Ethernet and IP have made it easy to standardize the lower layers of IP phone connectivity, the signaling is often still proprietary. At one time, a number of standards were contending to solve this problem, but the IETF's SIP (Session Initiation Protocol) has emerged as the winner. Many vendors are balking at adopting SIP, claiming it's still immature. Although some advanced features must still be nailed down, standards-based SIP phones are more functional than standard analog phones. For example, many have LCD screens with programmable soft keys, something usually found only on high-end digital sets. This hasn't gone unnoticed by carriers and ISPs getting into the VoIP services market--you'll be hard-pressed to find one that isn't using SIP technology to roll out services.

When we asked readers to name the biggest obstacle to deploying VoIP, only 7 percent cited lack of standards. The No. 1 answer? Cost, at 26 percent. The irony is that standards will drive down costs by giving incentives for third parties to mass produce phones. This is exactly why many vendors make their phones SIP-compatible, despite not supporting other vendors' phones with their switches. Once the standard is established, they could lose a source of revenue. However, this won't stop them from competing on the quality of their phones, another win for buyers.

It's important to ask any vendor claiming to support SIP what, exactly, that support entails. With which other products does its gear interoperate, and what options will it provide you with down the road? Ask for VoIP examples of third-party phones, switches or presence systems with which its offerings interoperate to ensure that "SIP-compliant" is more than a marketing buzzword.

We also asked readers how much they cared about being able to choose phones and applications from multiple vendors. Ninety percent consider this important, with about a third considering it "absolutely critical." On the other end of the spectrum, fewer than 5 percent said standards compliance is not important. When asked about the biggest roadblock to the adoption of SIP standards by vendors, almost half the respondents cited proprietary lock-in.

In fairness, when some vendors entered the VoIP market, there wasn't a solid standard, leaving them no choice but to move forward with proprietary technology. That has changed, however, and some vendors are catching on: Avaya and Nortel are pushing SIP support in their products, and we liked Nortel's announcement of its partnership with Polycom to offer a multimedia desktop and group conferencing system. SIP-based video, telephony presence and instant messaging will let Nortel and Polycom offer a best-of-breed, standards-based system that takes advantage of the companies' complementary strengths. We look forward to similar announcements from other vendors.

It's easy for service providers to get into the VoIP game by hosting switches in their data centers and providing services across dedicated lines. Comcast Cable, for example, made a quick entry into the market by acquiring VoIP provider GoBeam. Time Warner Cable has been testing VoIP services on its network and will likely roll them out this year.

Carriers, namely AT&T, MCI, SBC Communications, Southern Bell, Verizon and Qwest Communications International, are focusing on VoIP in a big way as well. MCI, in particular, has been a pioneer in offering SIP VoIP services. These carriers will have the advantage of quality control via QoS (Quality of Service) guarantees on their own networks.

But while off-loading the chore of implementing VoIP may be attractive, keep in mind that the biggest vulnerability is the physical connection between the provider and your location. If the line goes down, all calls will stop. If you can't afford an outage, make sure the provider has redundant, geographically diverse connectivity.

Another variation is to have a provider manage a VoIP switch located on your premises. You're relieved of the burden of hiring staff to run the system while maintaining some of the benefits of having your own IP PBX. For example, if you own the switch, you have more control over which applications and services are integrated. You also can take over control if the outsourcing arrangement doesn't work.

Some vendors are offering VoIP across the Internet. Its ubiquitous connectivity makes this easy, but since there's no quality guarantee, we recommend caution. The most notable player in this area is Vonage, which offers local phone numbers in most calling areas along with unlimited U.S. and Canadian long-distance calls; dirt-cheap international calls; and a host of features, including voicemails delivered via e-mail, three-way calling, caller ID and call forwarding, for $15 to $30 per month extra. For an additional $5, you could provision--online and in minutes--a phone number in another city tied directly to your phone. All this is done using SIP technology. Equivalent service on the PSTN would cost hundreds of dollars per month and could take weeks or months to provision. Vonage says it is signing up 20,000 customers per week.


Checklist of Basic Features

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We look forward to the day when this level of flexibility is tied to QoS guarantees, making these inexpensive services more appropriate for businesses. We say "more" appropriate, because we've talked to Internet telecommuters using VoIP who find that the flexibility and features outweigh the risk of decreased call quality.

VoIP and Wi-Fi

A number of vendors, such as Alcatel and Nortel, are pushing the benefits of running VoIP over 802.11 wireless networks. The premise is that it makes sense to take advantage of the proliferation of 802.11 access points within enterprises. Cell phone coverage is often spotty in buildings, and cell phone calls are a significant--and, in many cases, an uncontrolled--expense. We're even seeing SIP-based phones designed for this purpose, such as Pulver Innovations' $249.95 Wi-SIP phone. Additionally, any SIP soft phone running on a wireless-enabled laptop can use any Wi-Fi network to make calls.

There are gotchas with using Wi-Fi for voice calls, however. For instance, there's no way to control the quality of a wireless connection. A call made on a wireless network could be wiped out by someone downloading a large file. The IEEE 802.11e standard, which may be ratified by the end of this year, will attempt to address this problem by adding QoS. Meru Networks says it has solved this problem by incorporating algorithms into its access points that provide increased density of active clients and predictable voice and data QoS without any change to the clients (for our take on VoWLAN, see "Poised for Takeoff,").

Although it isn't necessarily time for us to rip out our phone systems to replace them with VoIP, it is time for us to take a serious look at the capabilities. You may see productivity benefits from VoIP features, such as presence and unified messaging. If you are about to replace an existing phone system, or are buying one for a new location, you would be remiss not to consider VoIP. Get quotes for both legacy and VoIP systems. And don't forget to factor in the costs you may incur upgrading your network to add the reliability and predictable performance that VoIP requires.

Peter Morrissey is a full-time faculty member of Syracuse University's School of Information Studies, and a contributing editor and columnist for Network Computing. Write to him at [email protected].

Our fictional insurer HaveNoFear needed to get lean and mean to fend off rivals looking to muscle in on its lucrative niche--indemnifying reality-TV producers from lawsuits by disgruntled or emotionally damaged competitors. One piece of its strategy was to implement a full-featured VoIP system. But because HNF was small--just 180 employees--the company's biggest fear was that it would be unable to afford some of the desired productivity-enhancing features, such as presence, unified messaging and automatic call redirection.

The company needn't have worried. As we note in "Holy Efficiency Edge!" the growing adoption of SIP (Session Initiation Protocol) should put downward pressure on prices by letting customers avoid proprietary lock-in. And while HNF is looking to keep its entire VoIP system in-house, service providers and carriers are rolling out hosted IP voice offerings. VoWLAN is making strides as well.

In "VoIP to the Rescue", we received RFP responses from Avaya, Alcatel, Interactive Intelligence, Nortel Networks, ShoreTel, Siemens and Zultys Technologies. We wouldn't eject any one from serious consideration, but Siemens' HiPath captured our Editor's Choice award because of its excellent presence application and full-featured PBX and conferencing system, all at the least expensive price in our roundup.

Want to experiment with standards-based VoIP? Check out Free World Dialup's gratis phone service, at fwd.pulver.com, where you can download software from various softphone vendors and make SIP calls over the Internet using the company's servers. Currently, you can only make free calls to other subscribers, but it's an excellent way to get hands-on experience with SIP-based VoIP, test SIP clients and let users try VoIP on for size.

To get more serious hands-on experience, download SIP server software. Pingtel recently announced it will release its Pingtel Sipxchange software into the open-source community, where those wishing to experiment with VoIP can do a pilot for very little cost. Pingtel, which also makes the Expressa phone, is hoping this model will encourage further VoIP innovation among open-source developers. Find out more about Pingtel's effort at www.sipfoundry.org.