IP Security (IPSec) is by no means your only option to secure communications on your wireless LAN (WLAN). Before you deploy IPSec, consider the type of applications that your wireless stations need to access.
For example, if the stations need to interact only with Web sites or Web-based applications (including file and print services over HTTP), then installing certificates on your Web sites to enable Secure Sockets Layer (SSL) is sufficient. If you run more traditional client-server applications that communicate with a Microsoft SQL Server database, change the transport protocol to one that supports encryption (e.g., select the Multiprotocol setting). If users of wireless stations send and receive email through SMTP, POP3, or IMAP4, force the stations to use those protocols over an SSL connection or issue certificates to users so that they can encrypt email messages. And you don't need to secure communications between wireless stations and domain controllers (DCs), because ordinary traffic, including authentication, is already secure—unless your DCs also act as file and print, database, Web, or application servers.