Solutions in this chapter:

• Overview of Content Filtering
• Overview of Attachment Scanning
• Installing and Configuring McAfee GroupShield
• Installing and Configuring Trend Micro ScanMail for Exchange Server
• Installing and Configuring Content Technologies MAILsweeper for Exchange 5.5
• Choosing Third-party Attack Detection and Scanning Services

Introduction

We looked briefly at content filtering in Chapter 9 during our discussion on securing Microsoft Exchange Server. In this chapter, we will focus more intently on scanning e-mails and attachments for questionable content. We will talk about the different ways in which filtering is done, what is looked for during the filtering process, and what is done with the e-mail once it s filtered. We will also look at the types of attachments that can be scanned and filtered, such as document, ActiveX, and Java files.

Many organizations employ firewalls and Internet proxies to protect access to their networks. However, they are still exposed to attack from viruses, spam, mail bombs, and other inappropriate content that can come through the door within e-mail. Without some type of content-filtering application to scan e-mail, corporations are wide open to productivity-robbing attacks from advertisers, malicious virus programmers, and pornography promoters.

Some e-mail servers are built with content filters. However, one of the more popular messaging platforms, Microsoft Exchange Server, does not come bundled with a content filter. In fact, most of our illustrations in this chapter will involve Exchange Server and the more popular third-party software packages used with it. Content scanning isn t done only at e-mail servers and e-mail gateways it...