Wireless Definition and Solutions

Wireless topics covering definition, objectives, systems and solutions.

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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.

Wireless gives people who spend most of their time in the field vital information that can create efficiencies, and save time and money, but office workers can also benefit. An executive with real-time access to e-mail from a mobile device can get to the next meeting and still get that important message instead of waiting at a desk.

What about security?

Security is one of the biggest barriers to any kind of wireless initiative—whether it's implementing a WLAN in a remote office or rolling out wireless handhelds with application capabilities such as e-mail or CRM data. The mobile security vendors are a force to be reckoned with in this space. The key for IT executives is to cut through the FUD and determine the real risks to a wireless initiative and the intended benefits. Then the decision becomes a simple risk management, cost-benefit equation.

Benefits of wireless communication

Wireless dramatically improves the convenience, reliability and timeliness of communication by allowing people to:

  • Remain persistently connected with others regardless of anyone's location and without being plugged into anything
  • Save time and money by shaving seconds off of regular tasks such as locating people, scanning items and receiving mission-critical alerts
  • Conduct daily chores effortlessly via a conveniently pocket-sized PDA
  • Reap the benefits of a rapid pace of innovation in a fast-growing market full of vendors scrambling to make people's lives easier

Challenges

  • So many choices—the options are many; the differences can be confusing
  • Wireless throughput is generally limited compared to the wired alternatives
  • Uncertainty as to which technologies will remain viable long-term. Each camp (CDMA and GSM) has several iterations of high-speed wireless service, with carriers choosing different versions and implementing them at different times. The situation prevents customers from counting on universal access to a given service.
  • Wireless security is lagging
  • Dropped connections reflect the inherent limitations of wireless signals easily obstructed by physical barriers such as tunnels, mountains and buildings, as well as radio noise and the absence of cellular towers in a given region
  • Small screens in PDAs and other wireless devices limit how much a user can view at once
  • Short battery lifespans mean that users must be conscientious about charging their batteries

Recent improvements

Both devices and network technologies have improved by leaps and bounds in the past year or so:

  • Wireless LANs have improved in the area of security
  • Devices now have color screens, more memory and faster processors, which devices such as BlackBerrys have incorporated into their newest designs
  • Cellular carriers now support IP packets, meaning data can pass over existing voice networks
  • Prices for both devices and network time are dropping between 15 percent and 20 percent each year
  • Many vendors, including Microsoft, Oracle and SAP, are building wireless functionality into new versions of their software; on the hardware side, Intel's Centrino processor now supplies built-in wireless support
  • Security is improving as vendors add security features to their wireless devices to compensate for the security limitations inherent in many legacy protocols. 802.11b showed up—with security and standards

Getting started

What's a good strategy for getting a wireless project off the ground?

Start by figuring out what kind of information needs to be accessed, by whom and from where.

Evaluate how easily it will be to access the information that is going to be sent out to wireless devices. Is the information coming from a variety of sources? Is the information too large to be conveniently accessed on a PDA or phone?

Start small, with a pilot project, but keep in mind that not all projects will be scalable for a larger rollout or more robust applications.

Keep realistic expectations in mind. Ask the following questions:

  • Coverage – how large an area am I asking my wireless to cover?
  • Speed and bandwidth needed to run an application-will I have enough?
  • Device interface-does the application work well on a small screen?
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Buzzwords

  • Bandwidth

    The total information flow on a telecommunications medium over a given time. The greater the bandwidth, the quicker the transmission or retrieval of information.

    Bandwidth is typically measured in increments of Kbps (kilobytes per second), Mbps (megabytes per second) or Gbps (gigabytes per second).

    A 56Kbs modem can easily move 16 kilobytes in one second.

  • BlackBerry

    BlackBerry provides a variety of wireless PDAs and software to keep mobile professionals connected to the people, data and resources they depend on. Its push-based wireless technology integrates e-mail, phone, SSMS, a browser, industry-specific applications and organizer applications on a single device. It also allows you to view e-mail attachments in popular document formats. BlackBerry supports various service providers, and 50 networks in 30 countries.

  • Bluetooth

    Bluetooth is an industry-standard specification for wireless networks, with a range of about 10 feet and a maximum throughput of about 1Mbps. A Bluetooth device, which incorporates a base-band processor, a radio and an antenna, uses radio signals to send information from one Bluetooth device to another through the air, at a frequency of 2.4 gigahertz.

  • Firewire

    IEEE 1394 (a.k.a. FireWire) is a type of cabling technology for transferring data to and from digital devices at high speed. Some professional digital cameras and memory card readers connect to the computer over FireWire. FireWire card readers are typically faster than those that connect via USB. FireWire was invented by Apple Computer but is now commonly used with Windows-based PCs as well.

  • GPRS

    GPRS is a digital cellular technology that transmits both voice and data, at a throughput of up to 100Kbps. Its range varies from several hundred yards to several miles, depending on the density of buildings and other obstructions. GPRS is a standard throughout Europe and widely deployed elsewhere in the world, including the United States and Canada.

  • PCS

    Much like a cellular technology, Personal Communications Services (PCS) send calls from transmitter to transmitter as a caller moves. The difference is that PCS uses its own network, not a cellular network, and offers fewer "blind spots" than cellular.

  • PDA

    A Personal Digital Assistant (PDA) is a handheld computer that provides a calendar and organizer for personal information. A PDA normally contains at least one database with names and addresses, to-do lists and a notepad. Some PDAs, such as the BlackBerry, provide phone and e-mail capabilities.

  • VoIP

    Voice over Internet Protocol is IP Telephony. It involves the transmission of telephone and fax calls over a data network like the Internet.

  • WAN

    Wide area network – can be wired or wireless

    Wired example: a network connecting the computer LANs in a company's multiple office locations

    Wireless example: Cellular phone network that covers areas as large as several countries

  • WAP

    Wireless Application Protocol (WAP) is a set of protocols used to transfer data to wireless devices. WAP-enabled devices provide wireless users with a limited version of the Web designed to work on the small black-and-white screens of phones and PDAs.

  • Wi-Fi

    Wireless fidelity (Wi-Fi) is another name for IEEE 802.11b, a trade term promulgated by the Wireless Ethernet Compatibility Alliance (WECA). "Wi-Fi" is used in place of 802.11b in the same way that "Ethernet" is used in place of IEEE 802.3. Products certified as Wi-Fi by WECA are interoperable with each other even if they are from different manufacturers. A user with a Wi-Fi product can use any brand of Access Point with any other brand of client hardware that is built to the Wi-Fi standard.

  • Wireless LAN

    A wireless LAN (WLAN) is a local area network (LAN) without wires (see LAN). WLANs have been around for more than a decade, but are just beginning to gain momentum because of falling costs and improved standards. WLANs transfer data through the air using radio frequencies instead of cables. They can reach a radius of 500 feet indoors and 1000 feet outdoors, but antennas, transmitters and other access devices can be used to widen that area. WLANs require a wired access point that plugs all the wireless devices into the wired network.

Hot questions

Anil Khatod, president and CEO of Alpharetta, Ga.-based AirDefense, answered questions about wireless technology. AirDefense is an innovator of wireless LAN security and operational support solutions.

Q: How will wireless technology overcome the limited channels and interference in highly dense areas?

A: Technology advancements in the form of dynamic RF management (intelligent power control and interference avoidance), along with spatial division multiplexing, can significantly expand the capacity available today. Further out, higher density modulation schemes and multi-radio, mesh network architectures may also come into play.

Within the enterprise, voice over IP (VoIP) may become the dominant application of wireless LANs, followed by traditional Web and e-mail usage. Hotspot applications will likely remain dominated by Internet access. Q: Is the security risk in wireless higher as compared to cabled network even when a similar degree of protection is provided in both cases by means of encryption or other such methods?

A: Yes, the implications of an untrusted physical layer are numerous. Many legacy protocols never considered these implications and may be vulnerable as a consequence without appropriate modification or configuration requirements. Further, the host or end-user is often the weakest link in the security chain and the open nature of wireless may exacerbate this weakness.

Q: What is the biggest mistake companies are making concerning the implementation of wireless?

A: The biggest mistake is not being aware of their wireless environment. Many secure wireless deployments ignore other devices that may be within or around the deployed environment. These devices include rogue APs and stations and other devices that existed prior to the wireless deployment. Having an ongoing awareness of all wireless devices, how they're behaving and interacting is essential for maintaining the security and operational stability of a wireless network.

Q: Can a wireless system be hidden from all discovery?

A: Some wireless protocols can be configured to not speak until spoken to. Bluetooth can be configured in such a way. However, by definition, 802.11a,b and g by protocol definition must make themselves known to devices that may communicate with them. If networks could be configured not to be discovered until a legitimate device attempts communication, as soon as they begin communication with that device at the very least their radio emissions would be detectable if not framed data.

Concealing a wireless network from discovery is typically accomplished through physical barriers such as window coatings or other RF barriers.

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Checklist—8 things you need to know

  1. Managing a wireless network is more difficult than managing its wired cousin; there are worries about performance, security, and pesky wireless-specific issues such as radio-signal and traffic management. Before deploying wireless LANs widely, CIOs must ensure they put in place the right management systems.
  2. Choose your battles carefully: Implement wireless only where the payoff would be greatest. Many companies start by equipping their traveling sales force with wireless devices.
  3. Upgrade Windows users to Windows XP, which provides wireless support that is superior to earlier Windows releases.
  4. Wireless applications should be integrated with their wired counterparts. For example, sales people who rely on BlackBerrys should be able to easily upload their BlackBerry-resident e-mails to the corporate e-mail server.
  5. Security is possibly the trickiest factor to finesse; make sure you observe best practices carefully.
  6. Most U.S.-based cellular networks are incompatible with other countries' networks. It might even make sense, for example, to equip your international sales force with a different cellular network than their domestic counterparts.
  7. Avoid dropped connections by choosing (or at least favoring) whichever vendor offers the best coverage – i.e., the most towers—in the regions that are most important to the best wireless candidates in your company. For example, Verizon is widely considered to offer the best coverage in New England.
  8. Study different vendors' roadmaps to prevent future surprises—see the section entitled "Tomorrow's Wireless Technology." For example, if you choose Nextel, will their recent merger with Sprint, a carrier whose CDMA technology is at odds with Nextel's Motorola iDen cellular technology, bode well for you?

Copyright © 2007 IDG Communications, Inc.

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