Introduction

Wireless networks represent one of the more exciting advances in networking technologies in recent years. By freeing network communications from the "tether," the physical cable that constrains access to the network, wireless technologies can produce large gains in productivity and can lower costs associated with wiring buildings for access to the network.

As with any new networking and computer technology, however, wireless networks introduce new security risks and concomitant challenges for the security administrator. When network communications are no longer bounded by wires, anyone can potentially listen to the network, connect to it, and gain access to it. Now, someone sitting in the parking lot outside an office or some other relatively nearby place can potentially gain access to the network. Furthermore, just as wireless networking standards are relatively new and immature, so too are the standards that govern security on wireless networks. In addition, the very newness of wireless networking contributes to widespread ignorance regarding its operation, attendant security risks, and available security measures to counter and reduce those risks.

As we pointed out earlier, effective security is the sum total of a well-planned and carefully implemented security infrastructure, which can include the use of smart cards, digital certificates, firewalls, encryption, and other measures. No wireless network, no matter how well secured, can add to the overall security of the network if due care has not been exercised to secure the entire network. In fact, the converse is true: a wireless network adds more security risks and...