When Will We Get Our Own WiMax Links?

Wi-Fi networks freed us from having to wire our offices and homes. Now WiMAX may free us from needing any wired connection to the Internet.  

If you want broadband Internet connectivity, chances are you use a DSL, or cable-modem-based landline connection at home or a T1, T3 or frame-relay at the office.

WiMAX technology promises to replace that last mile connection with a point-to-multipoint wireless connection in the same way that 802.11 Wi-Fi has replaced the wired LAN.

WiMAX, the commercial name for a variety of technologies that use the IEEE 802.16 standard, promises an open wireless standard that can deliver, in theory, up to 70M bps data throughput at ranges of up to 31 miles. As the IEEE is quick to point out though, those kinds of WiMAX ranges and speeds are myths. A more practical line of sight range might be 10M bps at 10 miles. In a city environment, realistically you'll be glad to see 10M bps at a mile range.

However, to get away from the line of sight requirements, when vendors today, such as the recent alliance of Sprint and Clearwire, talk about WiMAX, what they're actually thinking about deploying is Mobile WiMAX.

Mobile WiMAX is based on the IEEE 802.16e-2005 standard. This technology, in practice, should deliver 1 to 5M bps throughput at a range of about a mile. Higher, burst rate speeds, up to its maximum of 40M bps, may also be possible.

There's nothing new about point-to-multipoint microwave networks. Companies such as Alcatel-Lucent and Siemens have offered it for years, but their products relied on various proprietary technologies. The end result is that these wireless long-haul technologies have tended to only be used in vertical markets. WiMAX, on the other hand, with its standardized technology, offers the possibility of low-cost, standards-compliant components from multiple, competing suppliers.

WiMAX also lends itself to multiple uses. For example, 802.16 divides its MAC (media access control) layer into sub-layers. These sub-layers can support different transport protocols, such as IPv4; IPv6; ATM (asynchronous transfer mode) and voice. With MPLS (Multiprotocol Label Switching), vendors can allocate their WiMAX broadband capabilities dynamically. For a telecomm, this means that they can use WiMAX to offer customers an all-in-one wireless Internet, mobile voice, fixed voice, and multimedia package.