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Welcome to the Wireless World

David's article is an introduction to wireless LAN technology, walking lawyers through the basics of how wireless LANs work to what types of wireless technologies are available. He discusses WiFi and WiFi2, Bluetooth, and infrared wireless. The article first appeared in Law Office Computing.

The typical law office in 2002 has multiple computers wired together to communicate, share data, and access research resources. Local area networks (LANs) are the hallmark of the modern law office. They enable even a two-person firm to share information and access in ways that were possible in the past only by using a "sneaker" network - data transferred on foot.

Just as wired LANs are commonplace, a new technology for network communication is beginning to make inroads in businesses of all sizes. Wireless networking offers a flexible complement to a wired network and wireless products are finally reaching speeds and price levels that make it an affordable alternative. Law schools have been installing wireless LANs since 1998. Law firms and courts are beginning to adopt wireless LANS as well. There are good reasons why a wireless LAN could be in the future of your law office.

How a Wireless LAN Works

There are two types of wireless LANs. The first is an ad hoc network. This network is created at any time, anywhere there are two or more computers with wireless NICs. If Joe is in his office and Laura is down the hall in hers, and each has a wireless NIC in a laptop, Laura can transfer files to Joe via their informal, ad hoc network. The network disappears when Laura and Joe turn off their computers or physically move beyond the antenna transmission range, which is typically in the hundreds of feet.

The second type of wireless LAN is an infrastructure network. This is the typical method of installing a wireless LAN and involves an additional piece of hardware, beyond the requisite wireless NIC. The wireless NIC allows user-to-user direct transmissions. A wireless access point supports transmissions for many users simultaneously, far more than an ad hoc network can support. Access points are the one part of the wireless network that connects to your wired network, even if just to your Internet connection, via wire. The wireless NIC sends a data transmission to the access point, which relays it on to the relevant resource and then transmits the response back to the wireless NIC. Since the access point connects to the wired network, you can use your wireless NIC to transmit data to non-wireless users and computers as well as other wireless users.

There is one other difference between an infrastructure wireless network and a wired network. On a wired network, each computer has a guaranteed amount of bandwidth. For example, on a 100 Mbps wired network, every computer can potentially transmit up to 100 Mbps worth of data regardless of the number of simultaneous users. On a wireless network, the bandwidth available to a particular user will fluctuate depending on how many simultaneous users are using the same access point. Current wireless LAN access points can typically transmit 11 Mbps. If five computers request a Web page at exactly the same moment, they can each transmit and receive slightly more than 2 Mbps through that access point.

Wireless Technologies

There are two primary wireless technologies: infrared and radio frequency. Keep in mind that the wireless technology used in these LANs isn't the same as your wireless phone. The technology used in LANs provides speeds that are comparable to a wired network. Wireless phones still transmit at speeds approximating a dial-up modem's connection to the Internet. The most promising wireless telephone technology, 3G (or third generation) wireless will transmit at about 1/100th of current wireless LAN speeds. The focus is on radio frequency, or RF, wireless LANs largely because they offer the most potential and are seeing greater rates of adoption by organizations than infrared. It's important not to ignore infrared, or IR, wireless though. Wireless LANs are a complementary technology that can be used in your law office to make your wired network more flexible. In some cases you will be able to achieve your goals using IR which, albeit slower, still allows connectivity in a small environment.

Infrared Wireless

An IR wireless LAN uses infrared light to transmit data from one computer or device to another. The further apart the two computers are, the slower the transmission speed. Top speeds appear to be about 4 Mbps from a distance of about 10 feet. The distance limitation isn't a dramatic drawback because IR devices must be able to transmit "line of sight". Two IR wireless computers have to be able to "see" each other without any obstructions. Newer technology involving IR wireless access points allows for transmission beyond a room's walls, but the computer and access point must be able to communicate unobstructed.

These limitations are balanced by the secure nature of the transmissions. Data sent over IR continues to be more secure than other wireless data transmissions and this may weigh in favor of using IR wireless in your office. However, if you have more than two or three people who will be using wireless networking in your office, RF wireless is the better solution.

Radio Frequency Wireless

Radio frequency wireless LANs are increasingly popular because, unlike IR wireless and other wireless technologies, you can achieve speeds comparable to those on a wired network. False starts by the organizations that dictate how networks operate have complicated the picture, however, and led to a proliferation of RF wireless standards. The increasing predominance of the 802.11 standards has decreased this complexity, but it will be important, in evaluating which wireless LAN products are right for your office, to know about the alternatives.

IEEE 802.11

Unfortunately, the leading standard has the unwieldy name of "802.11". The Institute of Electrical and Electronic Engineers (IEEE) is responsible for creating standards for how networks operate. The 802 Committee is responsible for development of LAN standards. Their eleventh standard relates to wireless LANs, hence the 802.11 moniker. The original 802.11 standard was adopted in 1997 but wasn't very effective in gathering support. In 1997, most wired networks could transmit data at 10 Mbps. Wireless LANs using the 802.11 standard could only transmit at 1 Mbps. Technology companies designed wireless NICs to utilize the standard but added proprietary technology to increase the transmission speeds. The result was that only wireless network cards from the same vendor could communicate with on another, unlike wired networks to which you can connect practically any computer or printer with a network card.

High Rate Wireless: 802.11b

Wireless LANs took a leap forward in 1999 when IEEE adopted the 802.11a and 802.11b standards. These laid the foundation for widespread implementation of wireless LANs as well as outlining the technology’s future. Confusingly, 802.11b was implemented first while 802.11a -based technology is only now becoming available. For the foreseeable future, both technologies will be available. 802.11b is also called "High Rate" wireless. It was implemented first for a number of reasons. First, the wireless technology available in 1999 operated in the 2.4 GHz range of the radio spectrum. High Rate wireless technology also operates in the 2.4 GHz range, making it easier for technology manufacturers to update their technology. In addition, the 2.4 GHz range is available in almost every country for use by wireless networks, enhancing its popularity because products could be sold globally. High Rate LANs allow transmission of data up to 11 Mbps and, in the future, will be updated to as much as 25 Mbps.

WiFi2: 802.11a

802.11a is the more promising standard. New products implementing this technology are coming onto the market and, though more expensive than its 802.11b counterpart, it provides many enhancements over its predecessor. Unlike the High Rate wireless, 802.11a, nicknamed WiFi2 because it's the second "wireless fidelity" standard, will be able to reach speeds of 54 Mbps and will be updated to support speeds in excess of 100 Mbps. These speeds begin to approximate the typical Ethernet connection of the early 2000s but it seems inevitable that wireless LAN speeds will continue to trail those of wired LANs.

WiFi2 has also moved wireless LAN transmissions from the 2.4 GHz range of the radio spectrum to the 5 GHz range. This is important because the 5 GHz range is larger and there is more space both for higher transmission speeds and for avoiding conflicts with other wireless devices. The 2.4 GHz range is home to High Rate wireless, Bluetooth and proprietary wireless, baby monitors, some cordless telephones, and garage door openers, all of which use the spectrum. While the hopping technology in High Rate aids in avoiding colliding with other wireless, the inescapable fact is that the 2.4 GHz range's popularity will make it a very congested wireless space. The greater space available to WiFi2 will likely provide for future growth.

802.11 and Security

The most significant stumbling block for wireless networks has been the encryption of the data transmitted from the wireless NIC to the access point. 802.11 wireless networks use wired equivalent privacy (WEP) to encapsulate data and keep it from being accessed by an unauthorized user with wireless access. WEP, when activated on a wireless network, makes your network as secure as an unencrypted wired network. The standard provides 40-bit WEP encryption but this has been successfully compromised and does not necessarily protect you from hackers. While WEP is implemented on some products at stronger encryption levels, such as 128-bit encryption (also known as WEP2), it's still vulnerable. Some vendors have taken steps to implement a higher, proprietary level of security. Unfortunately, this is a step back toward the proprietary wireless of the late 1990s because only wireless equipment from the same manufacturer will support the enhanced security. If you take your wireless Cisco card and use it on the court's Orinoco wireless network, you will only use the lowest common security level available to both cards via the 802.11 standard.

IEEE is already at work on a security update for WEP, which is essentially a standardized version of the proprietary enhancements vendors are making. There are additional ways to block intrusion into your wireless LAN, including requiring computers that access the network to provide an approved hardware address, information that is individual to each NIC.

Personal Area Networks

A red herring in wireless networking is the appropriation of the term "wireless networking". Companies marketing wireless phones and other wireless devices have latched onto the hype surrounding anything wireless. While these devices can communicate wirelessly, they aren't truly able to replace and supplement your wired LAN. The closest technologies are those that create so-called "personal area networks". A personal area network is more truly a single computer that interacts with other devices - printer, scanner, fax machine, personal digital assistant (PDA) - via wireless connections rather than with other computers. A personal area network replaces the many wire connections between a computer and its peripherals, although in some cases it might also support a small computer network.

One method of creating a personal area network is to use IR wireless. Infrared is ideal because the physical obstructions that hinder it as a LAN technology are rarer in a personal area network environment. Additionally, it can reach speeds of up to 4 Mbps.

Bluetooth

It's worth mentioning what is perhaps the most hyped wireless personal area network technology: Bluetooth. This standard, named for a 10th Century king of Denmark, uses RF wireless to transmit data up to 30 feet at speeds up to 1 Mbps. Originally seen as a competitor to the 802.11 wireless standards, it has failed to live up to its promise primarily because Bluetooth products have been slow to appear on the market. The slow speeds and short distances Bluetooth can cover, and the momentum 802.11b and 802.11a appear to have gained are sealing Bluetooth's fate as a personal area network technology, whatever aspirations it might once have had. However, because it uses RF wireless, it's likely to supplant IR technology for personal area networking, because it needn't have "line of sight" to transmit data.

HomeRF and other proprietary technologies.

Other wireless standards and proprietary technologies are beginning to fade as the 802.11 wireless products gain ground. HomeRF was initially a slow (1-2 Mbps) RF wireless network that was intended for home users. Products like Intel's Anypoint wireless network rely on vendor-specific technology and are focused on home or very small businesses. Despite the move away from proprietary solutions, HomeRF and Intel’s Anypoint solution, might still be a suitable low budget, low traffic solution for the solo or home office.

Going Wireless: Considerations

The threshold question is whether your office can benefit by having a wireless LAN. The answer for lawyers may increasingly be "Yes". As more lawyers adopt laptops as their primary computer or rely on a handheld computer (Palm, Handspring, PocketPC), wireless networking can dramatically affect where and how lawyers do work. There are any number of reasons that you might want to implement a wireless network, including:

• Your law offices are in an older building where additional wiring or rewiring is expensive and a wireless network could provide you greater coverage at less cost;
• You and other lawyers and staff in your office primarily use laptops and could benefit from being able to take your laptop with you anywhere in the law office;
• Courts in your jurisdiction, your clients, or other sites you regularly visit (including Starbucks!) have installed wireless networking that would enhance your ability to provide legal services.

Resources to Connect

The first step is to determine what resources you will be using on the wireless network. This may impact what product you eventually select. Laptops are the most obvious users of wireless because their mobility offers the greatest benefit. If you have a mixture of desktops and laptops in your law office, you might leave your desktops wired to the network and provide wireless only for laptop users. Alternatively, you might only wire those desktops that are relatively immobile - reception desk, library terminals. The only other devices that can currently be connected to a wireless network are PDAs. Xircom's Wireless Springboard for Handspring Visors and Symbol's Wireless Networker for Pocket PCs are both 802.11b compliant.

Which Technology?

Once you have an idea of what you will be connecting, you can determine what type of wireless technology you will use. One of the 802.11 solutions is your best bet, unless you have a particular reason to use IR or a personal area network technology. If you don't need the speeds potentially available with 802.11a products, then the less expensive 802.11b technology may be the best choice. If you have an office that is likely to grow in size or if you want to plan for unseen network needs, 802.11a is the better option. Interoperability Since 1999 the issue of interoperability has largely disappeared. Until the security issues related to the 802.11 standards came to light, you could largely mix and match wireless equipment from different vendors with a good chance of success. A Cisco network card would have no problem transmitting data through an Apple Airport access point. The interoperability of wireless technology is overseen by the Wireless Ethernet Compatibility Alliance (WECA). Vendors submit wireless products to WECA for testing and WECA certifies qualifying products as having "wireless fidelity" or WiFi™. This is the origin of 802.11a's nickname, WiFi2. A baseline for any 802.11 wireless technology purchase is that the equipment be WiFi™ compliant. Non-802.11 technology isn't going to be interoperable in any event. The WiFi™ compliance ensures that the technology you buy today will work with emerging WiFi™ technology, perhaps from a better-priced competitor or an alternate company if your vendor goes out of business. It also increases the likelihood that you will be able to use court, client, and other wireless LANs. It underscores the importance of making the right decision on selecting 802.11b or 802.11a technology. The latter is more recent and isn't backward compatible with its sister standard. 802.11b equipment will almost certainly undergo enhancements in the future but it won't become compatible with 802.11a networks. An additional consideration is that, even though a wireless NIC may be WiFi™ compliant, the vendor may have made proprietary enhancements. Some vendors, for example, have enhanced the WEP security on their products. Two products from that vendor will use the higher security. The same wireless NIC will work on another network but, if the vendors are different, may only transmit at the weaker WEP security level.

Cost

Standardization has caused the prices of wireless networking equipment to plummet. While still more expensive than its wired counterpart, a wireless NIC or access point has become far more cost-effective. The comparison of prices for your hardware will show that wired hardware is typically cheaper. However, the cost savings you can realize when you eliminate the cost of installing wiring and network ports and any additional costs if you ever reconfigure your office – move your library shelves, add or subdivide offices, add additional network ports – can weigh in favor of wireless LANs. Wireless cards with proprietary, enhanced security or other features will sell for more than wireless cards from the same vendor that lack the enhancements. When you are shopping for a wireless product, make sure you are certain you have seen the entire line of products from that vendor. You should be certain you’ve seen the basic product as well as the premier, “gold” standard product.

Security

This is the greatest area of concern in relation to wireless networks. The technology has settled sufficiently that you can get reliable network access practically any product. The security issues can't be overstated. When you install a wireless network, you need to keep in mind that the network may well transmit beyond the walls of your law office. It could extend downstairs or next door to your neighbors, or onto the street where "war drivers" - hackers that drive around with wireless laptops seeking out unsecured wireless networks - can park and access your resources. The most important step is to ensure that you activate the security that is provided. Every WiFi™ compliant wireless network has at least 40-bit WEP available. One of the most common security issues is that this first line of defense hasn't been activated. It isn't bulletproof but it will dissuade the merely curious. All wireless NICs have a unique media access control address (MAC). Your access points can be configured to only allow the specific MAC addresses of your office’s users to have access. Each access point can include the list of all MAC addresses for your wireless users, providing a second obstacle to unauthorized users. The only way to ensure the same security level on your wireless network as on the wired is to implement a virtual private network or similar technology. This requires authentication of the computer and user, not just a handshake between your wireless antennas. If you decide to implement wireless, this may be a good time to audit the security on your wired network. This audit may point to a solution for issues on your wired network that would help to secure your wireless LAN access.

Wireless in the Future

The future looks bright for wireless networking and law firms. Our increasingly mobile profession can improve how and where they have access to their office network by adding wireless to the wired office. A wireless network should never entirely replace a wired network but always act as a complement to it. The next year or two will see data transmission speed gains and increasing price competitiveness for wireless components. Wireless networks will make further inroads into courts and other locations where lawyers can provide better service with increased network access. Security improvements will only serve to increase the momentum of the wireless network. Is it the "year of the wireless LAN" yet? We're probably still a year or so away from that. But wireless LAN technology has definitely arrived and may have a valuable role to play in the technology you use every day in your law office.