Wireless Definition and Solutions

Wireless topics covering definition, objectives, systems and solutions.

What does "wireless" mean?

Wireless means transmitting signals over invisible radio waves instead of wires. Garage door openers and television remote controls were the first wireless devices to become a part of everyday life. Now the cordless keyboard and mouse, PDAs, and digital and cellular phones are commonplace.

Wireless technologies are used for things as simple as making a phone call or as complex as letting the sales force get information from an ERP application.

Once reserved for only the most mission-critical and esoteric applications, wireless communication has entered the mainstream as vendors refine the throughput, stability, security and affordability of an ever-growing range of supported wireless applications. In the wireless world, your colleagues' whereabouts become totally transparent as you remain persistently connected with one another in real-time – even if some of your colleagues are flying cross-country. The ubiquity of wireless communication is confirmed by the results of a www.cio.com survey of CIOs:

  • 83% of CIOs have enabled wireless access to e-mail
  • 75% of respondents are currently undertaking a wireless project
  • 68% said wireless is either important or somewhat important
  • 16% cited wireless as extremely important to their current business goals
  • Almost 10% of CIOs are starting to pursue data-intensive wireless projects, such as access to CRM and ERP systems

For businesses, wireless technology means new ways to stay in touch with customers, suppliers and employees. The future of wireless lies in faster, more reliable methods of transferring data and, to a lesser extent, increased use of voice commands and audio improvements.

What's the difference between wireless and mobile?

Mobile just means portable. A laptop is a mobile device, as is a PDA or a cell phone. A desktop would be a mobile device if you had the inclination to carry it around with you. A wireless device has some sort of network connectivity. A cell phone is wireless, and a laptop or PDA would be wireless if they had a wireless modem. Similarly, applications are wireless when they connect and exchange data with a network.

Wireless can be divided into these categories:

  • Fixed wireless—the operation of wireless devices or systems in fixed locations, such as homes and offices. A typical example would be equipment connected to the Internet via specialized modems.
  • Mobile wireless—the use of wireless devices or systems aboard motorized, moving vehicles; examples include the automotive cell phone and personal communications services (PCS).
  • Portable wireless—the operation of autonomous, battery-powered wireless devices or systems outside the office, home or vehicle; examples include handheld cell phones and PCS units.
  • IR wireless—the use of devices that convey data via infrared radiation. Example: portable wireless devices that normally derive their power from batteries

Today's wireless technology—cellular networks

Four of the five North American cellular networks fall into two main camps: code division multiple access (CDMA) and global system for mobile communication (GSM):

  • Sprint PCS and Verizon Wireless offer CDMA2000 1xRTT networks in most areas. They provide throughput of about 30Kbps to 50Kbps. That's adequate for e-mail and short database queries, but little else.
  • Cingular Wireless and T-Mobile offer GSM general packet radio service (GPRS) in most areas, providing the same throughput of 30Kbps – 50Kbps.
  • Nextel Communications, the fifth major U.S. carrier, uses Motorola's iDen cellular technology, which offers throughput of about 35Kbps. Nextel's merger with Sprint likely means it will move to CDMA technologies.

Tomorrow's wireless technology

  • Sprint PCS and Verizon Wireless

    To provide greater bandwidth, Sprint PCS and Verizon Wireless are migrating to CDMA2000 1xEVDO, which offers throughput of 100 to 300Kbps, which is up to four times faster than the earlier generation. Verizon already offers the new service in 30 major U.S. cities (including New York, Atlanta and Los Angeles) and expects to make it available nationwide by the end of 2005. Sprint plans to launch EVDO service in 2005, but has not said which cities will get it first.

    One Verizon 1xEVDO customer, Optimus Solutions, claims connection speeds of about 250Kbps, which allows users to receive large files such as PowerPoint presentations quickly. While slower than a home broadband connection, Verizon's 1xEVDO networks are less expensive (at about $80 per month per user) than paying for broadband connectivity that confines users to hotels or Wi-Fi hot spots.

  • Cingular Wireless and T-Mobile

    Cingular and T-Mobile's next iteration, Enhanced Data GSM Environment (EDGE), offers throughput of 50Kbps to 200Kbps – significantly less than CDMA2000 1xEVDO. The version beyond that, UMTS, provides 100Kbps to 350Kbps speeds. But Cingular currently offers UMTS service in only six cities (with a national rollout slated for later this year), EDGE in about half its coverage area and GPRS, the slowest network, in the rest.

    T-Mobile, meanwhile, offers just GPRS and plans to offer UMTS service in 2007. But GSM does have an advantage: Although slower, GSM networks operate in much of the world, providing broadband access to global travelers.

  • Data-only connections

    Three new technologies provide data-only connections:

    • Flash orthogonal frequency division multiplexing (OFDM)
    • The Institute of Electrical and Electronics Engineers' (IEEE) 802.16 (popularly known as WiMax)
    • Universal Mobile Telecommunications System's telecommunications display device (UMTS-TDD)

It is not clear which vendors may be adopting any of these three technologies.


How do wireless networks work?

Wireless data is predominately transferred over two kinds of networks: wide area networks (WANs) and local area networks (LANs). These networks are similar to their wired counterparts, but they just use radio waves instead of copper or fiber.

WANs can cover areas as large as several countries. AT&T Wireless, Cingular Wireless, Sprint and Verizon and are among the carriers that use wireless WANs.

Wireless LANs (WLANs), already popular in airports, coffee shops and hotels, are often used to replace or enhance wired LANs. WLANs can cover 1.25 miles indoors and up to 4.35 miles outdoors in extreme cases, but work best in the 500-foot range. They may service a smaller area than their WAN cousins, but LANs can transfer data much faster, with speeds of 54Mbps now possible. Many companies are switching to WLANs for voice over IP.

More on LANs

Wireless LANs all use some standard in the 802.11 family to communicate. There's an 802.11 standard for just about every letter in the alphabet. You don't really need to worry about most of them - they are security and clarity standards that mean only that wireless LANs are getting even safer and easier to use. There are only three standards you really need to worry about:

802.11b—This protocol, which uses the 2.4GHz spectrum, dominated the market first, earning it the nickname Wi-Fi. It's a busy spectrum, full of baby monitors, cordless phones and microwave ovens, and the more traffic builds the greater the chance for interference and drops in speed. Today, service is good and speeds remain fast. An 802.11b user can get connection rates of up to 11Mbps from up to three different information sources at a time - for maximum throughput availability of 33Mbps - before interference becomes a problem.

802.11a—A competing wireless LAN standard that operates in the 5GHz spectrum allows for speeds of up to 54Mbps from up to eight different access points at a time, giving it a greater range and max speeds up to 13 times faster. However, in order to use 802.11a you need all of those access points. The primary reason to choose one is a need for lots of bandwidth, for example, for transmitting voice or video over your network. Since b is ubiquitous - and a and b aren't compatible - 802.11a equipment isn't good for portability.

802.11g—This is the next generation of 802.11b, promising the price and range of b (it operates on the same 2.4GHz spectrum) with the speed of a. It is compatible with existing b infrastructure and is generally believed to be the heir to most LAN connections.

More on WANs

The first-generation wireless WAN was analog voice (the earliest cell phones). The second generation was digital - more efficient cell phones that could move data at rates of 9.6Kbps to 14.4Kbps. Most U.S. carriers are now at 2.5 generation, or 2.5G transmission rates, which will carry data up to 114Kbps, but will most likely perform similar to a dial-up modem. Carriers have been pushing to 3G, which will include theoretical transmission rates of up to 2Mbps to 5Mbps, advanced roaming capabilities, as well as the sought after (by some) "always-on" potential.

Like LANs, WANs have many acronyms, mainly because carriers use different standards. Each works, but they don't always work with each other.

What have been the traditional hurdles to wireless adoption?

Real wireless projects depend on three elements: the device, the network (i.e. the WAN) and the application. If one of those elements isn't up to par, then the project won't work. No one uses cumbersome devices; people give up if they can't connect to the network, and there's no point in doing a project if you can't deliver the data. Until recently, most devices had small screens that made it hard to view data, they ran out of batteries quickly-sometimes wiping out all the information in the process-and they were expensive. Networks, meanwhile, were proprietary and expensive.

Those that succeeded fell into predictable categories. They were the companies that had large mobile workforces, depended on data from those workforces and, most importantly, could afford to invest in custom devices, proprietary coverage plans and homegrown applications. UPS is a great example. More common examples were trucking companies that tracked their drivers with GPS devices, shipping companies offering delivery confirmation, and utility companies whose repair crews collected large amounts of data about problems and fixes in the field.

Is the landscape any different today?

It is changing. Both devices and network technologies have improved by leaps and bounds in the past year or so. Devices now have color screens, more memory and faster processors, which means that people can actually use them. Also, 2.5G networks now support IP packets, meaning data can pass over existing voice networks. The result is better, more reliable coverage.

Prices for both devices and network time are dropping between 15 percent and 20 percent a year. There is still work to be done on the application side, but many vendors, such as Microsoft, Oracle and SAP are building wireless functionality into new versions of their software.

What it all boils down to is that wireless technology is now available off the shelf, and even companies with long-standing investments in custom-developed wireless systems are turning to commercial products and services.

What are the limitations of wireless?

When it comes to WANs, bandwidth is still limited. When transmitting data, users must sometimes send smaller bits of data so the information moves more quickly. The size of the device that's accessing the information is also still an issue. Even the most recent phones and PDAs have small screens - often only a couple of inches in diameter - and it is hard to read large documents on them.

Many applications need to be reconfigured if they are going to be used through wireless connections. Most client/server applications rely on a persistent connection, which is not the case with wireless. Transactional systems require safeguards for dropped wireless connections. Remedies for all of these shortcomings cost money.

Do I really need wireless?

Just because your company can go wireless doesn't mean it should—not every company needs wireless.

Critical, time-sensitive applications are the best candidates for WAN projects. If getting information in real-time makes or breaks a sale, give your salespeople access to that data. But remember that WANs are best suited for accessing small pieces of information because of bandwidth constraints.

Wireless LANs are often installed for convenience, such as when an enterprise doesn't want to wire the building, or when an IT staff is dispersed throughout the building. They are often used in hospitals, where doctors and clinicians can check in while on rounds or on the floor. Wireless LANs are faster and more reliable than WANs.

What about ROI?

Pinning down return on investment for wireless projects is hard. ROI can more easily be figured if a wireless project raises revenue or decreases cost, but most wireless projects improve productivity and lower stress, and that is hard to quantify. For example, a businessperson using a BlackBerry device can download e-mail throughout the day rather than spend an hour at night in his hotel room. That extra hour could be used to phone home or make more sales calls.

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