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WiMAX: the future of broadband?
LESS THAN 20 per cent of the US population, and an even smaller percentage of people across the world, have broadband access today. Why? Because existing technologies like DSL, cable and fixed wireless are plagued with high initial costs, problems with loop lengths, upstream upgrade issues, line-of-sight restrictions and poor scalability.What if these issues could be resolved with the help of a nomadic/mobile broadband internet that can be accessed anytime, anywhere at high speed, simply by plugging in? WiMAX — wireless Metropolitan Area Networks (MANs), based on the IEEE 802.16 family of standards — is just such a solution that will by the end of the year offer wireless broadband internet access to residences and businesses at relatively low cost.
This standard supports shared transfer rates of 75Mbps or less from a single base station, which can offer broadband access without requiring a physical ‘last-mile’ connection from the end-user to a service provider. Service delivery to end-clients is likely to be roughly 300Kbps for residences and 2Mbps for businesses.
The technology will be particularly beneficial to Pakistan’s rural areas and other locations where broadband access is not currently available. The current infrastructure owned by cable providers provides coverage to only limited areas, and much of it is suited only to cable television. Upgrades to make it capable of delivering broadband data service are expensive, and therefore, prohibitive in low-density population areas.
DSL has the limitation that end-users must be within about three miles of the PTC exchange or distribution point of a Local Loop operator. Thus, for many users, particularly those in rural locations, DSL is virtually not available.
The superior range of WiMAX connectivity and its ability to do without wired distribution media allow it to overcome these limitations. Although the optimal range is 4 to 6 miles at high throughputs, but at reduced throughputs the range could be increased to up to 30 miles. The relatively low cost of covering a distribution area with WiMAX service, relative to cable or DSL, will be an incentive to service providers to extend coverage to new business and residential customers.
While this technology may not provide universal broadband service, yet it should extend service areas substantially beyond their current limits and will be able to cover most of our population.
WiMAX also promises to provide rapid provisioning of broadband service. The PTCL routinely requires several months to provide new E1 lines and other enterprise-level data connections for business customers under best of circumstances, and installation costs tend to be high. The DSL operators are also restricted to provide higher rate connections only in areas where they have installed their equipment. The dependence on businesses of all sizes on such provisioning for mission-critical resources has grown dramatically in the past few years and will grow further once our businesses address the WTO issues.
The obstacles in terms of long installation lead-times and high provisioning costs will remain relatively high. The location of our domestic backbone along with main trunk routes makes it more imperative to take full advantage of this emerging technology for spreading the broadband to areas away from the trunk routes.
In late 2003, a schedule of development was announced at the Intel Developer Forum, stating that Intel will begin production of WiMAX silicon in 2004. Stationary broadband connectivity to businesses and homes will be provided by 802.16a (standard approved in January of 2003), followed by mobile access to laptops via 802.16e (standard pending). The 802.16a standard covers the frequency range of 2 to 11GHz, which allows the technology to operate without line-of-sight limitations. However, other developers have also made considerable progress, such as the Navini, Proxim and Alvarion.
More opportunities will arise for those developers who develop applications taking advantage of this new technology. Enterprise solutions for implementation, such as by field surveyors, news reporters, health visitors, utility company field personnel, delivery-men, and in our case the Nadra, will be required to get connected with their enterprise computers or with the world wide systems. VPN and other similar services will also be able to take advantage of this technology, though after a little retooling.
In most of Pakistan, wired infrastructure for the delivery of residential and business broadband does not exist or is unreliable. In order to extend internet services to our rural areas and in most urban areas, service providers must provide new infrastructure from the ground up, which drives the price of services up. This has been the main cause for low density of the telecom services in our country.
To achieve a reasonable profit margin and acceptable timeframe, infrastructure costs must be kept under tight control. The cost factor takes greater importance in sparsely populated areas, which are traditionally under-served by communications technology. Wireless last-mile technologies promise to make service delivery profitable in many regions where traditional wired technologies are impractical.
Our small-business market is currently served largely by point-to-point radio or DSL, and to a lesser extent, by cable networks for broadband connectivity. In addition to the location limitations already discussed, these technologies typically provide limited upstream bandwidth, which can have substantial limitation for many business clients, depending on their specific needs. Those businesses that plan to host web-based resources or plan to support a substantial remote-user base may find this limitation to be particularly significant. Moreover, since cable provider networks were put in place primarily to serve the cable television market, they are not available to many commercial locations.
WiMAX networks provide an alternative to these distribution channels, since they are free of the existing last-mile infrastructure and provide greater upstream bandwidth than cable and DSL. These networks are also highly scalable, since providers can add additional cells to a service area at a cost that is substantially lower than that required to extend a DSL or cable network.
In developed countries, the densely populated and business areas are largely already served by cable and/or DSL. Thus, new service modalities are likely to have a difficult time competing on those markets, where the customer bases are already well served. Thus, WiMAX is expected to thrive largely in rural and otherwise under-served areas, where the profit availability for providers is relatively low, which may hamper its adoption generally.
The situation in our country is quite the opposite; we do not have any recognizable broadband structure in cities or rural areas. Hence, WiMAX will have unopposed field.
How it works
WiMAX actually can provide two forms of wireless services: there is the non-line-of-sight, WiFi sort of service, where a small antenna on a computer connects to the tower. In this mode, WiMAX uses a lower frequency range — 2 to 11GHz (similar to WiFi). Lower wavelength transmissions are not as easily disrupted by physical obstructions — they are better able to bend around obstacles.
Then there is a line-of-sight service, where a fixed dish antenna points straight at the WiMAX tower from a rooftop or pole. The line-of-sight connection is stronger and more stable, so it’s able to send a lot of data with fewer errors. Line-of-sight transmissions use higher frequencies, with ranges reaching a possible 66 GHz. At higher frequencies, there is less interference and lots more bandwidth. WiFi-style access will be limited to a 4 to 6 mile radius (perhaps 25 square miles or 65 square km of coverage, which is similar in range to a cellphone zone).
Through the stronger line-of-sight antennas, the WiMAX transmitting station would send data to WiMAX-enabled computers or routers set up within the transmitter’s 30mile radius (3,600 square miles or 9,300 square km of coverage). This is what allows WiMAX to achieve its maximum range.
An opportunity
By considerably lessening the limitations of limited mobile bandwidth and range, widespread adoption of wireless MANs will foster new markets for mobilized software. As business customers adopt WiMAX service, demand will grow for a wide array of mobilized business solutions, especially on the basis of the 802.16e specification, which will provide service directly to end-user mobile devices from central base stations. Businesses will be able to provide connectivity directly to field personnel over a wide territory on a more widespread basis than has been common thus far.
The high bandwidth and range of WiMAX-based services, relative to other wireless technologies, is likely to create demand for mobilized software solutions in industries that currently do not make widespread use of them. Service technicians, field sales personnel, and maintenance crews for everything from construction equipment to computer networks will be more able to access central business systems from the field.
That adoption, in turn, will help to build general demand for mobilized solutions, building on the already increasing market awareness of mobilized software’s desirability. WiMAX Vehicular Mobility Standard of 250Kph will open new doors to newer development. Thus, the rise of wireless MANs is expected to drive customer expectations that business solutions in general should possess mobilized capabilities. Client software increasingly must possess the ability to seamlessly accommodate sporadic connectivity, to cache relevant data from central networks, and to provide robust data synchronization with back-end systems. As customer expectations for such functionality continue to become the norm, they emerge as a locus of competitive advantage for those developers who have positioned themselves to benefit from this trend.
Conclusion
WiMAX promises to expand the availability of broadband service to residences and businesses that are currently under-served, including low-density rural locations in developed countries, and to open up a new era for the rapid growth of broadband in Pakistan. It will also provide a flexible solution to end-users for whom current provisioning timeframes are prohibitive, or for whom wired infrastructure is not available.
From the perspective of service providers, the WiMAX standard provides robust support for multiple service levels with a minimum of hardware requirements. The ‘adaptive modulation’ capability of the technology allows modulation schemes to be assigned dynamically, making automatic tradeoffs between range and throughput and increasing service levels to end-users.
Flexible quality of service support allows carriers to tailor services for the specific needs of different media, such as voice, video, and general data, with regard to latency versus reliable packet transmission. Developers, service operators and hardware manufacturers must call themselves to action in building wireless broadband solutions and devices around international standards. Such standards reduce costs and foster economies of scale by removing the need for multiple parties to create the technology’s building blocks independently. By ensuring interoperability between services and solutions from different providers, the investment risk to all concerned is also reduced.
The writer is secretary of the Internet Service Providers Association of Pakistan
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