Jul 03 2007

Discovering the Wonders of WiMAX

Cities and counties are beginning to take a chance on 802.16 technology to build high-speed municipal wireless networks.

Cities and counties are beginning to take a chance on 802.16 technology to build high-speed municipal wireless networks.

For nearly three years, information technology officials in Grand Rapids, Mich., diligently planned to build a Wi-Fi network throughout the city's 45 square miles. The technology, attractive because of its wide acceptance and low cost, seemed the perfect match for the community seeking to use ubiquitous wireless Internet connectivity to stimulate economic development, improve public safety and increase productivity among mobile city employees.

Eight competing vendors even built Wi-Fi hot spots around town to demonstrate their technology's benefits. But when decision time came last December, the city chose WiMAX, the 802.16 standard for wireless broadband. It was an eleventh-hour verdict, but when Grand Rapids officials toured three U.S. cities to test municipal wireless networks, they were blown away by WiMAX's capabilities.

"With Wi-Fi, we were challenged to make and keep a connection," says Sally Wesorick, wireless project manager for the city of Grand Rapids. "But with WiMAX, we did everything we could to lose a connection, driving into parking lots, areas with foliage, and then 70 m.p.h. on a highway -- and we stayed connected. We were amazed the technology was so robust. It was clearly the best solution for our city."

WiMAX is an emerging last-mile technology that allows local governments to build city or countywide wireless broadband networks that provide ultra-fast Internet connection speeds and reach greater distances than Wi-Fi networks.

802.11 Wi-Fi, originally designed for home and office networks, is limited to 100 to 300 feet, while WiMAX theoretically has a range of up to 30 miles. But in typical deployments, when buildings, trees, hills and users' quality of service are taken into account, most WiMAX deployments will support a range of between three to five miles, says Daryl Schoolar, a senior analyst within the Networking Group at In-Stat in Scottsdale, Ariz.


WiMAX supports Advanced Encryption Standard and Triple DES encryption.

WiMAX's superior reach is one reason Grand Rapids chose the technology. Rather than installing and managing 2,000 Wi-Fi access points, its WiMAX network will only need 15 to 20 WiMAX transmitting towers, says the city's IT Director Thomas McQuillan.

WiMAX can theoretically offer speeds of up to 70 megabits per second. But in practical usage, when the number of users sharing the bandwidth is taken into account, the technology will offer speeds of between 512 kilobits per second, which is comparable to DSL or cable Internet access, to 4mbps, which is more than twice as fast as a T1 line, Schoolar says.

A WiMAX network can serve as a local government's main network, or as a backup network in case its main fiber-optic cable network is incapacitated due to a disaster. With WiMAX, governments can provide high-speed Internet access to its buildings at a cheaper rate than subscribing to T1 lines. It's also a cost-effective way to provide businesses and residents with broadband access, particularly in rural areas where it's too costly to lay fiber.

While WiMAX is seen as a Wi-Fi replacement for governments seeking to build municipal wireless networks, the two technologies are also complementary. For example, a city can deploy Wi-Fi hot spots on a WiMAX network to give Internet connectivity to mobile employees, businesses and residents. Early adopters have taken different approaches to building and managing their WiMAX networks.

A Nascent Mobile Market

WiMAX comes in two varieties. Fixed WiMAX, otherwise known as 802.16-2004 or 802.16d, provides wireless Internet access in fixed locations, such as homes and offices. Mobile WiMAX, or 802.16e-2005, supports mobile applications such as those used by law enforcement officers riding in patrol cars. Mobile WiMAX, which will support cell phones and personal digital assistants, will also support fixed wireless.

Karl Edwards, cofounder and president of wireless consulting firm Excelsio Communications in Alpharetta, Ga., says he expects Mobile WiMAX will play a significant role in the broadband market, but adoption is still in its infancy because few products are available yet.

Vendors are racing to build Mobile WiMAX products, from transmitting towers to wireless notebook PC cards. Once wares are certified as standards compliant and become available later this year and early next year, the technology will begin to take off, he says.

"The big boom will start in 2008," In-Stat Senior Analyst Daryl Schoolar agrees.

Successful Partnership in Allegany County

In 2001, Allegany County in the foothills of the Appalachian Mountains in western Maryland used pre-standard WiMAX equipment to provide high-speed Internet access to the county's government buildings, schools and libraries. The county manages the network, but has granted local Internet service providers access to offer broadband services to the county's residences and businesses.

The county built its $4.7 million WiMAX network in partnership with Allegany County Public Schools, the Allegany County Library System and the city of Cumberland. The four entities pooled their IT expertise and received grants from the Appalachian Regional Commission, the state and the federal government to build the wireless network covering 525 miles of the mostly rural county in the northwest corner of Maryland.

The alternative was spending $680 million to build a fiber-optic communications network to meet the community's needs, says Beth Thomas, the county's information technology coordinator. "It's been an extremely cost-effective telecommunications backbone for public agencies," she says.

The core of the network, called AllCoNet2, features 16 wireless radio towers, supporting Asynchronous Transfer Mode, Ethernet and other broadband services. As a result, the network provides government agencies and the community with new and legacy telecommunications services, such as T1 and T3 services, that it needs, Thomas says.

Today, the network provides high-speed Internet access and Internet Protocol telephony to Allegany County's government buildings. The county streams video of government meetings on the Web. Law enforcement officers can access the regional incident reporting system and national crime database from their patrol cars. The county also uses video conferencing between courts and detention centers, so prisoners can attend hearings without the cost of traveling to the courthouses, Thomas says.

T1 line subscriptions for the county's six libraries would have cost $5,000 a month, a fee the library system could not afford, says Robert Hall, the library system's network administrator. Now the library gets 3mbps speeds at no cost. "We run everything, from our Web site, circulation system, accounting and phone systems, with this huge pipe," he says.

Overall, the county government saves $160,000 a year, while the county school district saves $400,000 in telecommunications spending per year, Thomas says. Other subscribers to the network include local towns, cities, state and regional government agencies and nonprofit organizations. These subscribers pay a nominal $420 annual fee.

Build or Lease?

A WiMAX network will run on the licensed 2.5 gigahertz band. Most of the licenses today are owned by service providers Sprint, Nextel and Clearwire. Local governments can build networks by partnering with existing spectrum owners or they can simply lease service from service providers, says wireless consultant Karl Edwards of Excelsio Communications.

Connecting to Fiber-less Areas of Corpus Christi

The city of Corpus Christi, Texas, used a mix of Wi-Fi and pre-standard WiMAX technologies to build a municipal wireless network in 2005, but recently sold it to service provider EarthLink, which is now providing wireless service to the city and the community. "We wanted to make sure we built the network out citywide and once we did, we didn't want to burden the taxpayers to run a business, so selling to EarthLink was the answer to our problems," explains Leonard Scott, business unit manager for Corpus Christi's wireless data deployments.

Corpus Christi, which has a large fiber-optic network that covers most of the 135 square-mile city, used pre-standard WiMAX to provide broadband access to the western and eastern portions of the city that had no fiber, Scott says.

For example, in the eastern part of Corpus Christi, the city deployed a point-to-point solution, in which one WiMAX base station is pointed to another base station seven miles away, he says. The city then installed Wi-Fi hot spots on the WiMAX network, allowing city employees, businesses and residents to connect via their Wi-Fi-enabled computers.

The WiMAX network, which cost about $400,000, serves as the backhaul -- or the primary link to a wired network -- for the city's Wi-Fi network. It also serves as a backup network in case the city's fiber network goes down in a disaster.

The city currently uses the wireless network for public safety and for improved efficiency of its public works employees. For example, if a water line breaks, public works employees on the scene can pull up geographic information systems maps and access their applications on their notebooks.

Scott says it's difficult to quantify return on investment. The city has saved money using WiMAX to replace T1 lines in remote offices in the western and eastern portions of the city, but "there's no ROI to public safety and the figures are not in on public works yet," he says.

Grand Rapids on the Front Edge

Grand Rapids partnered with start-up service provider Clearwire to build and operate a WiMAX network, which is expected to go live by year's end. In the contract, city government agencies will essentially get WiMAX for free, while Clearwire will generate revenue by offering businesses and consumers broadband access through a subscription-based model.

Grand Rapids will also use the WiMAX network for public safety, public works and land management, McQuillan says.

The city's IT department is currently Web-enabling its city applications, so employees can wirelessly access their applications on their notebooks. McQuillan says he isn't concerned that he's deploying cutting-edge technology.

"We may be on the front edge of the curve, but we believe the rest of the industry will move toward WiMAX," McQuillan says. "It's the right solution for us and we're confident that it will be a success."

WiMAX at a Glance

A WiMAX system features a WiMAX transmitting tower and a WiMAX receiver. One WiMAX tower, connected to a high-speed wired connection, can point to other WiMAX towers to create the network. A WiMAX receiver allows buildings or users to receive high-speed Internet access. The receiver comes in multiple forms, such as an outdoor device with an antenna and receiver, an indoor modem or a wireless PCMIA card.

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