Wi-Fi

Preparing for the next generation of wireless: WiMAX

Learn about the emerging WiMAX wireless standard.
The wireless industry is constantly changing, and each passing year brings major advances. Read Where Wireless Networks are Going to find out about advances in the U.S.-based wireless cellular networks – including a look on security, reliability, and overall experience.

Wireless networking, in the form of 802.11a, b, and g has started to revolutionize networking in business. It has given greater freedom to end users and allowed network administrators to offer new services and do more with their networks. As good as it is however, 802.11x is plagued by limitations that prevent it from being an answer for network administrators that need a longer-distance networking solution. That's where WiMAX comes in. Here's what this emerging technology will do for you.

What's wrong with plain old 802.11?
802.11x has its share of challenges and weaknesses. The three biggest weaknesses of 802.11x include:
  • Security
  • The need for a line of sight to the base station, which itself is connected to the physical backbone
  • Poor range

With regard to security, because packets go through the air, they can be captured or at least intercepted by a third party. This is a major “no-no” when it comes to a given business’s data integrity. Although 802.11x supports both WEP and WPA for data encryption to help secure packets as they're being transmitted, neither protocol is 100 percent secure.

802.11x wireless needs line-of-sight because the radio frequencies it uses don’t go through buildings well. A good analogy for this fact is the decreasing signal quality on your car radio as you drive through a long tunnel. If the tunnel is long enough, the radio signal will disappear altogether.

With Wi-Fi's relatively poor range, up to 1000 ft. in open areas and 300-500 ft. in built up areas, its usage is basically limited to inside building or between nearby buildings. Interference issues with cordless phones and microwave ovens operating on the 2.4-Ghz frequency can also negatively impact the range of 802.11b and 802.11g.

Enter WiMAX
WiMAX is potentially the new Goliath of wireless networking. I say potentially because it’s not available commercially yet (more on this below). Intel is a major force behind the creation and promotion of WiMAX, along with Nokia and Fujitsu and various other companies.

WiMAX is defined in the IEEE’s 802.16x standard and uses the 10-66 Ghz band. Various taskforces are working on getting it extended into the 2-11 Ghz range, but if this happens, it could affect wireless communications already in those bandwidths.

WiMAX’s best features are much overall performance. WiMAX will be able to pump data at a rate of up to approximately 70 Mbps at a range of up to 30 miles! Also, line-of-sight is not an absolute necessity. In effect, this means that if WiMAX comes to commercial fruition at some point soon, then the perennial issue of “the last mile” will have been solved and businesses in rural and remote locations will finally be able to buy a broadband WiMAX connection.

70 Mbps of bandwidth using one sector of a WiMAX base station is roughly equivalent to sixty T1 connections. 802.16 base stations are initially expected to come with six sectors! Think how much data you can send to branch offices in a metropolitan area without having to invest in land lines.

In regards to security, well, there isn’t too much information on that side of things yet, seeing as the technology is more or less still in its infancy. However, I know I will not be the only person who suggests to the developers of WiMAX that they better get some heavy-duty security protocols sorted out BEFORE the widespread sale begins.

WiMAX hurdles
Even though WiMAX will solve a lot of problems for businesses, it's not here yet. Anand Chandresekher, general manager of Intel’s Mobile Platforms Group predicts that although the standard was only really finalized in January 2003, the first slew of WiMAX products aimed specifically at service providers, may be available in the second half of 2004.

Initially he thinks that these products will be used chiefly to overcome the “last mile” problem, and consumer devices will come along a little later. He cites an interesting example of two markets, South Korea and Taiwan, which both have very high broadband-penetration rates in the general population. The adoption of WiMAX in these markets would foster greater competition and perhaps ultimately, greater price-fairness for consumers because non-cable-based providers will at last be on an even keel with their “cabled” competitors.

Various analysts predict that WiMAX will also be a direct competitor for the 3G wireless standard, as applied to cell phones. It is too early to tell but it is certainly true that with such high bandwidth capabilities, WiMAX offers some very attractive possibilities for the widespread adoption of VoIP technologies. If this happens, then telecoms and cable companies are going to get a serious run for their money as consumers bail out of costly airtime contracts in favor of cheaper services offered under the WiMAX umbrella.

There are three main hurdles which need to be overcome on the road towards “WiMAXification.” First, the 802.16x standard is large and complex and offers a host of development opportunities. An example is the choice of building IP-centric or ATM-centric systems; this depends on the needs of customers which are difficult to evaluate when a technology is emerging. Companies wishing to develop 802.16x products have to decide whether they want to offer a system which offers the whole spectrum of WiMAX capabilities (expensive, but guarantees compliance with the IEEE directive) or just a subset of them aimed at specific needs of target customer groups.

The “subset approach” runs the risk of non-compliance, but perhaps more serious, a lack of interoperability between systems from different vendors could arise. Interoperability has become somewhat of a Holy Grail of late, so this is a major decision for a manufacturer to make, and it has certainly affected the speed of WiMAX development.

Secondly, there is a lack of testing standards and no one has really agreed what such standards should include. Proper testing and adherence to testing standards for reasons of compliance is a very good idea because it applies a benchmark for products. It also means that systems from different manufacturers get tested in the same way so the playing field remains level.

Finally, if 802.16x equipment manufacturers decide to take the subset-of-features approach for reasons of economy, then there must exist a method to identify exactly which 802.16 subset(s) these products actually comply with. This will enable system integrators to pick and choose additional options, safe in the knowledge that they will still comply and be interoperable with the systems they have already implemented.

In economic terms, here’s an example: say I have an 802.16 product which conforms to standard A. The product contains 802.16 features-subsets B, C and D and was built by Company X. I now want to add features E and F to my product so that I can offer more services. If I know that I can buy these features more cheaply from Company Y than from Company X and that features E and F also conform to Standard A, then I am not going to have a problem with my investment. If such a system of compliance didn’t exist I would be taking a much greater risk.

Finding out more
When WiMAX becomes a reality, you'll definitely want to investigate it if you have remote sites in a metropolitan area. As products become reality, we'll go into greater detail about them here. If you want more information about WiMAX, you can visit the WiMAX Web site.
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