Internet & Intranet Security

OVERVIEW

In Part II we focus on firewall technologies that can be used to provide access control services for corporate intranets. We start with an advertising query and answer that Trusted Information Systems, Inc.^[1], put on its Web site in 1997 to promote its Gauntlet Internet Firewall System:

What do the CIA, MGM/Universal Studios, and the Nation of Islam have in common?

— Their Web sites were hacked and vandalized in 1996.

Against this background, Trusted Information Systems, Inc., suggested two conclusions that may be drawn:

1. One must protect a Web site.

2. One must use a Gauntlet Internet Firewall System to do so.

While one can agree with the first conclusion, the second one is not very obvious and was mainly drawn by marketing people at Trusted Information Systems, Inc. In fact, the Gauntlet Internet Firewall System as it was marketed by Trusted Information Systems, Inc., in 1997 is no longer available today (the product is now called Gauntlet Firewall and marketed by Network Associates, Inc.). As we explain in Part II, firewall technologies are very mature today, and many sophisticated implementations and products are available that compete with one another for the market share.

The aim of this chapter is to introduce the various firewall technologies that populate the Internet security market. More specifically, we overview and briefly discuss the rationale and the basic principles of firewalls in Section 7.1, elaborate on the basic components of a firewall configuration (i.e., packet filters and application gateways) in Section 7.2, and give some sources for further information in Section 7.3.

^[1]Trusted Information Systems, Inc., was later acquired by Network Associates, Inc.