All four major IM services allow you to create a personal profile in which you describe yourself and your interests, including your name, gender, age, home address, phone number, and e-mail address. This is information that stalkers, identity thieves, spammers, and other online wolves on the prowl can use to target you. Leave your IM profiles blank; if the fields must be filled in, enter fictitious data. To view and change your profile in AIM 5.2, choose My AIM, Edit Profile; in ICQ Pro and Lite, select Main, View/Change My Details; in MSN Messenger 6.1 or Windows Messenger, choose Tools, Options, Personal and click Edit Profile; and in Yahoo Messenger, select Login, Edit My Contact Info.
No matter how low an IM profile you maintain, the medium remains inherently insecure. Anyone with access to the network between your PC and the IM service's host computer can intercept your log-in and message traffic. If your relationship with IM is easy come, easy go, that may not be a big deal. But if your IM activity is business-related, very personal, or otherwise sensitive, you may want to encrypt your transmissions for privacy. Starting with version 5.2.3211, AIM allows you to digitally sign and encrypt your chat and file transfers by using a personal digital certificate. Verisign sells these certificates (which you download to your computer as a file) for $15 per year. To purchase a certificate in AIM 5.2, choose My AIM, Edit Options, Edit Preferences, select Security at the bottom of the Category list, and click Add.
None of the other native IM clients offer encryption. But Trillian Basic and Pro have a built-in encryption feature called SecureIM that works with both AIM and ICQ accounts. To enable SecureIM, click the large globe button at the bottom of the Trillian contact list and choose Preferences. Scroll down to the Chatting Services section in the left panel, and select Misc under either the AIM branch or the ICQ branch (see FIGURE 3
Last, if you want to secure all of your IM activity with encryption and a host of other safeguards, consider installing Zone Labs' IMsecure utility. You can switch from the free version of the program to a 15-day trial of IMsecure Pro with a single click (see FIGURE 4