As with many other firms and companies, we are looking at implementing Wireless LANs, or WiFi (the Trademarked name given by Wireless Ethernet Compliance Alliance to wireless networks operating with the IEEE 802.11b standard). Like many others, we question whether we implement it now or wait for the next standard. We are not new to wireless technology and have implemented wireless LANS in the past, albeit on a small-scale isolated to a single department or small remote site, and we used 802.11b. Later this year, we will be implementing wireless on an entire floor. Picking the right wireless standard may prove daunting, as you examine the many standards available or soon to be available.

802.11b, running on a 2.4GHz band, has been around for some time and would be a fairly easy implementation. It does, however, offer only 11Mbps connections and the number of users that can connect to one access point is small. In addition, 802.11b uses CCK (Complementary Code Keying) technology uses WEP (Wireless Equivalent Privacy) security technology. Given that 802.11b is in widespread use, it was a strong contender for our project until research showed the other 802.11 standards.

In addition to 802.11b, 802.11a should be considered. 802.11a is running on a 5GHz band and reports speeds up to 54Mbps. Like 802.11b, 802.11a uses WEP technology for security but increases encryption to 152-bit. Compared to "b", "a" reports to offer more channels, a wider band, more users per access point and more access points with less interference. Unlike "b", which uses CCK, "a" uses ODFM (Orthogonal Frequency Division Multiplexing), an encoding method for 802.11a. ODFM uses the spectrum efficiently by spacing channels closer together, thereby requiring less bandwidth for overhead. 802.11a, however, is not backward compatible with 802.11b, and our traveling users would experience issues if they wanted to use public access points (at airports, hotels, etc.) equipped with 802.11b.

There is another future contender, 802.11g, which is said to combine the best of 802.11a and 802.11b. "G" may not be out until Q1 2003, at the earliest. "G" is a result of IEEE's task group G. In early 2000, the IEEE formed Task Group G to explore the feasibility of increasing the speed of wireless technology in the 2.4GHz band with speeds over 20Mbps. Since 802.11a operates at 5GHz and is not interoperable with 802.11b, the IEEE felt that a faster technology was needed in the 2.4GHz arena. The 802.11g IEEE scope states that it is intended to enhance the performance and possible applications of 802.11b by increasing their data rates. 802.11g runs on a 2.4GHz band and promises speeds faster than 802.11b but slower than 802.11a. 802.11g, similar to "a", uses ODFM. "G" is also targeting to be backward compatible to 802.11a and 802.11b standards.

If only it was as easy as picking from the three wireless protocols, "a", "b" or "g". As our research progressed, we saw many references to 802.11 as alphabet soup, which is fairly accurate. As you have also probably read in other trade magazines, there are other letters, or standards, that are currently underway. These are 802.11e, f, h and i. These standards will be out over the next couple of years, some sooner than others. In addition, a number of the upcoming standards may not be wireless protocols, per se, but more along the lines of a set of enhancements for the "a", "b", and "g". For example, according to the IEEE, the purpose of 802.11e is to enhance the current 802.11 MAC (Medium Access Control) to expand support for LAN applications with Quality of Service requirements and enhance the capabilities and efficiency of the protocol. Example applications using 802.11 that will benefit from this will include voice, audio and video, video conferencing and media stream distribution.

The IEEE states that 802.11f's scope is to develop recommended practices for an Inter-Access Point Protocol (IAPP), which provides the necessary capabilities to achieve multi-vendor Access Point interoperability across a distribution system supporting 802.11 Wireless LAN links.

802.11h will build on and overlay 802.11a. The purpose of "h" is to enhance the current MAC and PHY (Physical Layer) with network management and control extensions for spectrum and transmit power management. In addition, this new spec will work on providing improvements in channel coverage (Dynamic Channel Selection) and transmit at the minimum necessary power level using transmit power control mechanisms (TPC).

Given the security issues associated with WEP on Wireless LANs, the IEEE Task Group I is focusing on improving the technology and enhancing the security and authentication mechanisms of 802.11. This standard will be known as 802.11i. The draft, finalized in January 2002, is looking for a security algorithm called Temporal Key Integrity Protocol or TKIP. This new protocol was developed with the help of some of the encryption experts that exposed WEP's vulnerabilities. TKIP is a rapid rekeying protocol that changes the encryption key every 10,000 packets. The IEEE does not view TKIP as the long-term solution to replace WEP. There is currently work being done on an encryption algorithm based on AES (Advanced Encryption Standard), which is the same security protocol sponsored by the National Institute of Standards. AES is reported to be coming out during the first half of 2003.

To deal with security, the IEEE has also drafted the 802.1x standard. The 802.1x standard, originally designed for wired Ethernet, is also applicable in the wireless arena. This standard enhances the security of wireless networks. It provides port-level authentication, which allows a user to be authenticated by a central authority. "X" is a mechanism to transport EAP (Extensible Authentication Protocol, RFC 2284) packets over an 802 link layer. By using EAP, a wireless access point authenticates a wireless NIC by consulting an authentication server.

With everything available, or soon to be available, for a successful wireless LAN implementation, the various standards and, more importantly, the security associated with the 802.11 technologies, must be researched and understood. The vast amount of documentation in this area continues to grow, as well as the many debates surrounding the security. The standards associated with the 802.11 technologies are truly an alphabet soup. As it continues to evolve and improve, let us hope that choosing which standard to use becomes less complicated than it is today.