Given the trade-off eWEEK Labs has seen between price and performance in GSM and CDMA2000 wireless access solutions, administrators must continue to cast an eye to the future for robust solutions that are also cost-effective.
Existing UMTS (Universal Mobile Telecommunications System) systems, such as those offered by AT&T Wireless, provide the best download throughput weve seen from cellular devices, and we expect further improvements to the underlying GSM (Global System for Mobile Communications) architecture to have a significant commercial impact in the near future.
HSDPA (High Speed Downlink Packet Access), a software upgrade to WCDMA (Wideband Code Division Multiple Access), is an asymmetric data transmission technique expected to deliver a download capacity of 2M bps to 3M bps and an uplink speed of 384K bps. Cingular Wireless LLC is expected to conduct initial trials of HSDPA next year, with wider deployment in 2006.
However, getting the most buzz in the mobile-data-access industry right now is 802.16e, the mobile version of WiMax (Worldwide Interoperability for Microwave Access). WiMax has significant backing from Intel Corp., and the fixed-point variety, 802.16a, has already been ratified. The mobile version of the standard is expected to be ratified early next year, with consumer products available in 2006.
WiMax, a method of broadband wireless access, uses frequency bands between 2GHz and 11GHz and does not require line of sight to the base station. Each WiMax base station will theoretically have a range of 50 kilometers, serving thousands of concurrent connections under ideal circumstances.
802.20 is another fledgling standard designed for mobile data access. Unlike WiMax, which relies on a limited number of base stations in a metropolitan area, 802.20 is a more cell-like option that is designed for high-speed mobility and promises throughput exceeding 1M bps.
Flarion Technologies Inc., a major proponent of 802.20, has been testing its FLASH-OFDM (Fast Low-latency Access with Seamless Handoff Orthogonal Frequency Division Multiplexing) technology with Nextel Communications Inc. However, the standards proceedings are not far along, so theres no guarantee that Flarions technology will ultimately form the basis of the standard.
Both 802.16e and 802.20 could also be hampered by carrier adoption rates. Mobile device connectivity for high user densities will require a significant infrastructure build-out, and carriers may ultimately view this deployment as an unnecessary duplication.
Of course, the unquenchable thirst for unfettered mobile access to data stems, in part, from the rapid proliferation of 802.11-based WLAN (wireless LAN) technologies in the home, the workplace and public hot spots. Indeed, the steady increase of Wi-Fi hot spots in public locations has fostered expectations of being able to connect to the Internet from anywhere. However, relying on public hot spots is a dicey proposition because coverage and throughput will be unpredictable and access could require payment to several entities managing the hot spots.
There are also significant costs for providers associated with maintaining 802.11 hot spots on a wide scale, as each cell requires its own Internet backhaul connection. This makes it difficult to provide unified access on a metropolitan basis. Maintaining fiber, T-1 or broadband connections to every cell simply isnt cost-effective on a large scale.
Wireless mesh networks may provide some relief to this latter dilemma by using wireless links to intelligently connect multiple access points in different locations to only a few backhaul connections. With this technology, access devices not only accept and process wireless client signals but also have the intelligence to find the shortest wireless path back to an Internet connection.
Interestingly, the fixed-point variety of WiMax could easily complement wireless mesh networks by providing the backhaul connection to the Internet. Hot-spot providers could reduce the installation and ongoing costs of maintaining a wired connection by using WiMax to wirelessly connect the hot spot to the Internet.
Technical Analyst Andrew Garcia can be reached at [email protected].