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Today, we’re use Wi-Fi for most of our laptop computer networking needs. In the next few years, though, we may be moving to the 4G technologies of WiMAX and LTE.

You might think that you wouldn’t need to worry with any new wireless technologies for your laptop, after 802.11n, with its 100-Megabit per second (Mbps) speeds, finally became a standard. You’d be wrong. Two new technologies, Worldwide Interoperability for Microwave Access (WiMAX), also called 802.16e, and Long Term Evolution (LTE), already are beginning to offer computer road warriors new wireless choices.

However, neither one will bring users a significantly faster network experience. In practice, both WiMAX and LTE top out at around 100Mbps. The real difference between these technologies is that instead of access point ranges measured in dozens of meters, these two standards can reach over 50 kilometers. How would you like to use a single “Wi-Fi hotspot” that can keep you connected at home, at the office, at your favorite coffee shop — and on the road between all these places? That’s the promise of both WiMAX and LTE.

Of the two technologies, WiMAX is the more mature. Numerous vendors have already released WiMAX network interface cards (NICs), which are certified by the WiMAX Forum industry consortium as compliant with IEEE standards and thus interoperable. WiMAX is already well accepted in Asia and, with the support of many smaller telecomm firms and the Intel, Google, and Sprint-supported Clear, it’s moving into major U.S. cities.

A WiMAX Primer for the Technically-Inclined

WiMAX allows data transport over multiple broad frequency ranges. This lets the technology avoid using frequencies that would interfere with other wireless networks. Like 802.11a, 802.11g, and 802.11n, WiMAX uses orthogonal frequency division multiplexing (OFDM) to increase bandwidth by splitting broad channels into multiple narrowband channels — each using a different frequency — that can then carry different parts of a message simultaneously.

In addition, taking a page from 802.11n, WiMAX uses multiple-input, multiple-output technology (MIMO) to increase both bandwidth and range. MIMO takes advantage of multipath interference. This kind of interference is what happens when transmitted signals reflect off objects and take multiple paths to their destination. If you’ve listened to a radio station’s signal wax and wane as you move towards the end of a tunnel, you’ve heard multipath interference. With standard antennas, such as those on your car, the signals arrive out of phase and interfere with one another. MIMO systems employ multiple antennas to use these reflected signals as additional simultaneous transmission channels. In brief, MIMO knits the disparate signals together to produce a single, stronger signal.

If it’s so much like 802.11n, you may be wondering, what’s the difference between them. The short, and most important answer, is power. A WiMAX base station typically transmits at 20 watts. 802.11n transmits at 50 milliwatts (mW), 250mW or 1 Watt.

Unlike Wi-Fi, WiMAX comes with quality of service (QoS) built-in. A WiMAX access point assigns each participating device its own access slot, which can expand or shrink depending on network usage.

WiMAX operates at a variety of frequencies. In the Asia-Pacific region, it operates at 2.4GHz; it uses 2.5 GHz in the Americas, and 5.5 GHz in the European Union. This means that you won’t be able to use your WiMAX NIC that works fine in, say, Portland, Oregon, if you take it to Tokyo Japan.

Wherever you go, in theory, WiMAX can pump out up to 100Mbps. In practice, like any Wi-Fi technologies, you only see numbers like those in a lab. Realistically, the Clear network delivers from 13Mbps to 2Mbps download speeds. Uploading is another matter. There, you can expect to see an average data transmission rate of 800 Kilobits per second (Kbps). That may not sound too impressive until you consider those are the speeds you can see driving around a city without ever having to login to another access point with every block you travel.

The Light Overview of LTE

While WiMAX comes from the data networking world, LTE’s history takes it back to the mobile phone GSM‘s General Packet Radio Service (GPRS). In many ways, the two technologies look a lot like each other. Both use OFDM and MIMO. Unlike WiMAX, though, LTE only uses OFDM for downlinks.

Coming as it does from the mobile voice world, a big part of LTE’s challenge has been moving to an Internet Protocol (IP) network architecture. So, for example, while WiMAX supports Voice over Internet Protocol (VoIP) as a matter of course, LTE designers are still working on supporting voice over packets. At the same time. LTE is meant to be backwards compatible with 3G and 2G systems. Ideally, vendors want to deploy devices that work on LTE/3G or even LTE/3G/2G networks.

The upside of this approach is that LTE “networks,” as they’re rolled out, will be able to work in more areas than WiMAX. The downside is that they’ll do so by sinking back to 3 and 2G Kbps speeds.

LTE can work at a variety of frequencies, but most of the interest from its supporters, such as AT&T and Verizon, is in the 700 megahertz and 2.5GHz ranges. LTE supporters claim that their networks will work even faster than WiMAX and with less latency. Verizon claims that users will see a much more modest 5 to 12 Mbps on the down-link and 2 to 5 Mbps on the up-link.

While LTE has the support of most of the telecomm companies, it’s also been lagging behind WiMAX in deployments. For example, while WiMAX is now available in many U.S. cities, Verizon only has two trial deployments, in Boston and Seattle. AT&T hasn’t even gotten that far.

What It Means for You

To use either technology, you almost certainly need to buy a new NIC. Windows 7 doesn’t come with built-in support for either WiMAX or LTE, so you’ll need the appropriate hardware drivers. While that was something of a problem in the early days of Windows 7, vendors are now shipping Windows 7 drivers.

Once equipped, using either standard is much like using a Wi-Fi network that requires a Web-based login. After you’re online you can use the connection just as you would any other network connection. For instance, you can use Secure Remote Connection over either one.

The vendors behind both technologies will be pushing them forward as last-mile Internet connections. While that might be fine if your company has any rural locations, for most offices the existing Internet backbone will almost certainly be faster, not to mention more secure.

Where WiMAX and LTE will be important is primarily for your mobile users. Thanks to the gigantic size of the technologies’ network footprint, your workers will be able to stay hooked up to the corporate network without constantly having to log back on.

As WiMAX and LTE begin to achieve broad market penetration you may want to look into dropping commercial Wi-Fi hotspot contracts. While neither of the pair are going to be threatening users who want the fastest possible wireless connection, for companies and employees who want “good-enough” wireless connectivity bundled with mobile phone coverage, WiMAX and LTE are going to develop as compelling alternatives.

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