When wireless worlds collide

Next-generation wireless LANs and WANs are on a collision course that will alter the mobile landscape forever. What should enterprises do to get ready?

2008 will be a year of tough decisions for enterprise IT executives trying to scope out a wireless strategy that takes into account exciting new technologies like 802.11n, 4G, WiMAX, dual-mode handsets, voice over Wi-Fi and in-building cellular.


Find out some tips for deploying 802.11n and what you should ask a vendor about 802.11n.


These new technologies will emerge and converge in 2008, which means IT departments need to build a comprehensive mobility strategy that spans LANs, WANs, mobile devices and applications. And that strategy needs to take into account the wild card of cellular carriers offering open access service plans for the first time ever.

With so many of these technologies still in their infancy, 2008 will not be a year of full-out deployments. But it will be a year to develop a long-term plan, to start putting together wireless RFPs and to make the necessary infrastructure upgrades.

IT wish lists:• Flat per-month, per-user worldwide cellular rates from service aggregators.• Pooled buckets of cellular voice minutes shared internationally.• Greater choice in unlocked mobile phones that are portable from network to network.

Commercial deployments of 802.11n LANs, 4G mobile WANs and fixed-mobile convergence (FMC) are expected to get under way late in the year, so enterprises need to start making some decisions rather quickly. For example:

Mobile voice. Companies must decide how they plan to provide ubiquitous in-building voice coverage. Do you go with Wi-Fi or cellular? You need to make that decision so you can determine the appropriate mix of handsets for your organization going forward.• 802.11n. Next-generation high-speed WLANs are shipping ahead of formal standards. Don't jump in all at once. But don't ignore 802.11n either. Begin adding 802.11n gear conservatively as you open up new offices, retire legacy products, require spot network performance improvements or unwire your access point network by using an 802.11n mesh.(Learn more about Wireless LAN products from our Wireless LAN Buyer's Guide.)Mobile WAN. WiMAX services with 2M to 4Mbps per-user speeds will go commercial this year. In addition, open-access initiatives from Verizon Wireless, Sprint, Clearwire and the winners of federal auction of the C block of the 700MHz wireless spectrum (now underway), might fundamentally impact your mobile procurements.• Convergence. Build a mobile convergence plan starting with the features you need today. Will extending PBX numbers to mobile users suffice? Or do you require unified e-mail and voice mail systems, corporate directory access, presence capabilities and video mail? Do users need automatic signal handoff from WLAN to mobile WAN? The answers to these questions will determine your potential vendor partners.

Let’s take a closer look at each of these areas and determine which technology is a go for 2008 and which should be on your radar screen for 2009 and beyond.

Voice: Wi-Fi or cellular?

In most organizations, some subset of users likely needs to be accessible by phone when away from their desks. You might decide that the productivity benefits of improved voice accessibility merits blanketing your organization with wireless coverage. You can do this using Wi-Fi or cellular technology. Your choice will be affected by site size, convergence plan, handset choices and even your revenue clout with your cellular carrier.

Voice over Wi-Fi. Many organizations have installed 802.11a/b/g networks. However, most support data in selected areas, without the dense coverage required to reliably support real-time voice conversations throughout a building's nooks and crannies. So one option is to invest in expanding the Wi-Fi infrastructure everywhere. Voice over Wi-Fi is attractive, in part, because it carries no usage fees.

One sticking point is that voice over Wi-Fi technology is still not very mature. A number of IEEE 802.11 standards relevant to voice have not been finalized, including those for fast secure roaming among access points and load balancing. So vendors have proprietary ways of supporting voice reliably over Wi-Fi. In fact, the Wi-Fi Alliance is not even slated to begin voice interoperability testing of Wi-Fi devices until mid-2008.

The many faces of mobile convergence
VendorPBX agnosticSingle- number reachExtension of PBX features/ unified communicationsAutomatic Wi-Fi-to-cellular handoffDual-mode handset /mobile operating-system support
Agito Networks*YesYesYesYesSymbian, Windows Mobile
Aruba**YesYesYesYesNokia E series and Windows Mobile
Ascendent/RIMYesYesYesNoSingle-number reach: any; unified communications: BlackBerry
AvayaNoYesYesYesSymbian and Windows Mobile or BlackBerry, Palm and Java
CiscoNoYesYesNoBlackBerry, Nokia E series
DiVitasYesYesYesYesNokia E series and Windows Mobile
FirstHandYesYesYesShips Q1 '08BlackBerry, Nokia E series and Windows Mobile
NortelNoYesYesNoBlackBerry, Nokia E series and Windows Mobile
SiemensYesYesYesYesNokia E series

* At press time, system due to ship Q1 Õ08 ** At press time, system due to ship January 2008

Stan Schatt, a vice president at ABI Research, advises holding off on voice over Wi-Fi "unless you are in certain key industries where the benefits are immediate."

For example, he notes that healthcare, retail and manufacturing environments are inherently mobile. So the benefits of voice over Wi-Fi in those organizations likely outweigh being locked into a single-vendor solution until standards and testing are complete.

So, unless you're in one of those industries, your best bet is to hold off on voice over Wi-Fi until the technology matures some.

Deploying In-Building Cellular Systems. An alternative to voice over Wi-Fi is using the cellular network indoors. While voice over Wi-Fi avoids indoor cellular usage charges, some carriers do have rudimentary service plans that lower the prices of indoor cellular calls made in certain corporate locations. AT&T's OfficeReach is one.

Indoor signal reception is the primary challenge. Without enhancement, indoor cellular coverage can range from intermittent to nonexistent, depending on how the building is architected and where the nearest cell tower is located. However, large enterprises can boost reception using distributed antenna systems (DAS) coupled with small carrier base stations.

Procuring RF base stations and associated DASs costs about $150,000 to $300,000 in locations of less than a million square feet. However, if you are a large company with hefty traffic volumes, your carrier(s) might very well pick up the cost of an in-building system for you.

One worldwide, Washington-based consumer products company estimates it would cost another $400,000 to $500,000 to enhance its wireless data LAN sufficiently for voice support. Instead, the company turned to an in-building system to boost cellular signals. The system cost $750,000, but the company's mobile operator picked up the tab and manages the network to ensure continued cellular revenues.

Smaller companies with tighter budgets and with less than 50,000-square feet to cover might opt for an intelligent repeater that picks up a signal from an existing nearby outdoor cell tower. This is a comparatively inexpensive alternative, usually costing less than $10,000 for product and installation.

Handset strategies. Coming up with the right handset plan is key, because you don't want to overspend on handsets. This can occur when employees end up with more devices than needed and monthly fees get buried in individual expense reports. To get your arms around handset deployment and management, centralize handset procurement and group users into categories based on mobility requirements:

• Those who must be accessible by phone inside and outside the office are candidates for dual-mode cellular/Wi-Fi phones. These might be salespeople and business executives who regularly visit customers and business partners. There are about 100 varieties of dual-mode handsets available worldwide and about 50 in the United States, according to Farpoint Group, a wireless consultancy.

None yet support next-generation 802.11n WLAN technology, though 802.11n is expected in dual-mode handsets this year. When investigating dual-mode phones, consider whether you will soon require full Wi-Fi-to-cellular seamless roaming. The reason is that you will need to make sure that the dual-mode handset you choose is supported by your FMC supplier.• Those who are internally mobile but don't make business calls outside the facility are candidates for Wi-Fi single-mode phones. They might include shift workers, such as nurses or personnel on a retail floor or in a warehouse.• Those who are externally mobile and don't need coverage inside office facilities are candidates for single-mode cellular phones. This group includes field service workers.

Many users in the last two categories are likely to require rugged phones to prevent damage and downtime. So you can begin filtering your list based on how many rugged phones you need, then compare features based on the requirements of each specific user group.

MIMOgration

Controversy persists over when enterprises should migrate to high-capacity 802.11n or MIMO products, the new generation of Wi-Fi that supports 300Mbps data rates.

The 802.11n standard won't be ratified until at least this fall. However, many enterprise-class Wi-Fi vendors — Aruba Networks, Bluesocket, Cisco, Colubris, Meru, Nortel, Trapeze Networks and Xirrus — have announced the availability of pre-standard 802.11n access points already. Wi-Fi veteran Motorola/Symbol and start-up Aerohive Networks plan to ship Draft 2.0-compliant access points during the first half of this year, and Extricom has yet to announce 802.11n plans. At press time, the only Wi-Fi Alliance-certified Draft 2.0, enterprise 802.11n access points were those from Cisco and Meru.

Today's 802.11n WLANs yield a four- to six-fold performance benefit over 802.11g, according to the latest Farpoint Group benchmarks. And 802.11n increases aggregate system capacity, "allowing more people onto the network without their work getting slowed down by others sharing the network," says Bill McFarland, CTO at WLAN chipmaker Atheros.

Lenovo and HP make 802.11n-enabled laptops today, and more Lenovo and new Dell models are expected soon, McFarland says.

However, just 1% of about 300 WLAN professionals surveyed by the Kubernan analyst and consulting firm in April 2007 indicated near-term plans for 802.11n, with most saying they preferred to wait for formal standards.

Action items for 2008 • Prepare for 802.11n with enhancements to WLAN controllers, wiring closet switches, and Power-over-Ethernet switches. Issue RFP.• Install 802.11n access points where you need greater throughput; in smaller, all-wireless offices; and possibly as a mesh access points backbone.• Group users into categories of those needing dual-mode, Wi-Fi-only, cellular-only and desktop-only handsets.• Plot convergence strategy and examine FMC offerings from specialized companies, IP PBX companies and WLAN makers.

The leading candidates for pervasive 802.11n deployments this year are higher education and healthcare, ABI's Schatt says. "802.11g isn't adequate for large lecture halls, and universities rarely wait for standards." Indeed, 802.11n deployments are already underway at Carnegie Mellon, Brigham Young, Ohio State and a number of other universities.

Meanwhile, healthcare is starting to send X-rays wirelessly "so they really do need the bandwidth," Schatt says.

But for most traditional IT shops, a full-on 802.11n rollout is looking more like a project for 2009.

The mobile WAN

New generations of mobile WAN technology with higher speeds and IP at their core are hitting the streets. The evolution of mobile WAN technologies affects new investments in wireless handsets and laptops, and forthcoming open-access service models will add choices to how businesses buy mobile services.

Most notably, WiMAX services will emerge in 2008 offering download speeds of as much as 4Mbps. Sprint and Clearwire have been the U.S. mobile WiMAX favorites because of their ambitious partnership to reach 100 million people in the United States with their Xohm WiMAX services in 2008. (Learn more about WiMAX products from our WiMAX Buyer's Guide.)

At press time, Sprint and Clearwire were proceeding with this goal, albeit having ditched an earlier plan to combine their networks. In addition, Sprint's financial troubles and replacement of its CEO, WiMAX enthusiast Gary Foresee, with industry veteran Dan Hesse, could mean the company will revisit its commitment to WiMAX.

WiMAX chipsets will become embedded in dual-mode laptops and handsets this year. Also, in-building cellular DAS providers LGC Wireless and Mobile Access have said they will support WiMAX in their systems. But analysts have mixed views about its uptake.

"WiMAX [service] will be available in reasonable volumes in 2008," says Craig Mathias of the Farpoint Group. "It might be worth experimenting with WiMAX in as many cities this year as possible to see how well it works."

Daryl Schoolar, senior analyst at In-Stat, is more cautious. "I'd wait to see what Sprint says in the first quarter before making any kind of purchase around WiMAX."

Sprint and Clearwire had outlined an open-access service model similar to that mandated for use in the commercial 22MHz spectrum block of the 700MHz band. In addition, Verizon Wireless has announced that it will provide open access to its existing EV-DO network in early 2008.

Open access would topple traditional U.S. cellular walled gardens, whereby carriers restrict devices, device features and applications, and third-party content access. In an open-access environment, users will have much more flexibility with their devices and, presumably, access to a slew of innovative new applications.

Devices used with open services will become more expensive, though, as operators will no longer subsidize them in return for a lengthy service contract. Many enterprises say it's worth the price to be able to use a device on any compatible network around the world and have access to all features and functions inherent to the phone. In addition, data usage with open services could become metered in the United States, a pricing model Verizon has said it will adopt, though Mathias dismisses as "not the world we are living in today."

The uncertainty surrounding the availability of a pervasive WiMAX network in the United States throws into question the dual-mode devices enterprises select. Wi-Fi is likely to be one of the embedded radios, including those supporting 802.11n, Schatt says.

But which 3G or 4G WAN radio should you choose, given the blurry state of 3G to 4G network transitions? Among the candidates: 500K to 700Kbps EV-DO Rev A; 700K to 1.4Mbps High-Speed Packet Access (HSPA); and WiMAX.

EV-DO is available throughout North America. HSPA runs on 128 commercial networks worldwide reaching at least 5 million users, according to the GSM Association. The WiMAX Forum estimates that more than 300 operators in more than 65 countries have deployed mobile WiMAX pilots.

Generally, embedded radios afford better reception than external clients, which can also become damaged and lost. However, if you don't envision upgrading mobile devices very often, choosing a PC Card or USB device that can be swapped out for different technologies as they mature makes sense.

Convergence considerations

You may require different degrees of convergence, depending on employee profile. Enabling a single business PBX number to ring multiple handsets is available from a number of sources, likely including your PBX supplier. More sophisticated unified communications requires a smartphone with special client software that has been integrated with your PBX. (Learn more about Unified Communications products from our Unified Communications Buyer's Guide.)

Chart of Wireless FMC subscribers

If you also require seamless inter-network handoff so users can roam among different mobile networks without dropping phone calls or data sessions, you must decide whether to turn to a specialized CPE maker, your PBX supplier or, possibly, a forthcoming carrier service.

There are many decisions to be made and migration plans to write. 2008 will be the time to begin fitting the various pieces of the converged mobile LAN-WAN puzzle together so you can do just that.

Wexler is a freelance technology editor/writer based in California’s Silicon Valley. Reach her at joanie@jwexler.com.

Learn more about this topic

 
1 2 3 4 5 Page
Join the discussion
Be the first to comment on this article. Our Commenting Policies