Fortifying your Firewall By Peter Morrissey   Wouldn't it be nice if securing your network against unauthorized Internet or intranet access was as easy as finding the best firewall for your money, plugging it in and moving on to your next networking challenge? Dream on. The reality is not that simple. Even firewalls that have endured stringent testing to earn industry certification are not guaranteed to protect your network from harm. For one thing, firewalls have to be installed correctly. For another, it's a sad fact of life that the odds are fairly good that eventually someone will find a novel way to undermine your defenses. However, a good firewall usually will make this more of an effort than it is worth. To view the Report card. Although firewall selection, installation and administration involve many rather complex and subtle technical and political issues, this security measure is likely to be one of your primary lines of defense against improper access to sensitive corporate data. Most of the firewalls we tested here use a method called "proxying" to screen data going into and out of the network. Proxies generate a much finer level of control than a router or packet filter. Of the firewalls we tested, only CheckPoint Software Technologies' FireWall-1 products do not use proxies; instead, they use Multilayer Stateful Inspection, which is a filtering technology that is much more advanced than packet filtering and may provide better performance than proxying. Also hot on the firewall scene are GUIs that simplify administration. A pretty GUI will not make your networ k more secure, but a well-designed one can ease the administrative burden and illustrate how well the firewall has implemented your security policy. All the products we evaluated have effective GUIs, with those in our winners--FireWall-1 Unix and CyberGuard--doing an especially good job. We were equally impressed with other improvements in CyberGuard, which was purely text-based a year ago. Surpassing even FireWall-1, which has always had one of the best designed GUIs in the industry, CyberGuard now lets you configure network interfaces with IP addresses and add static routes by filling out simple forms. Secure Computing Corp.'s BorderWare and Technologic's Interceptor use Web clients for administration, making it possible to perform this function from Unix, a PC or a Macintosh and generally ensuring consistency of the interface from one product to another. Chances are, most of these machines have the necessary browse r installed. This is convenient, but firewall administration is not apt to benefit from widespread access as much as other applications would. We found BorderWare and Interceptor to be much easier to administer than a text or command-line interface, but they were not very intuitive. In choosing firewalls for this round of testing, we started by getting the latest list of products to receive certification from the National Computer Security Association (www.ncsa.com). NCSA's testing is quite thorough. Its certification program is devoted to ensuring that firewalls meet minimum requirements for reliable protection. The agency scans each firewall it considers to make sure the firewall performs as advertised. The agency also verifies that Internet applications continue to function as expected. Once a specific version of software is certified by the NCSA, you will have to monitor the agency's Web page or check with the firewall vendor for updates. We were also anxious to ascertain whether any of these prod ucts could encrypt selected communications or support virtual private networks (VPNs). Because IPsec is supposed to provide a standardized method for encryption as long as you use manual key exchange, we were especially interested in products that advertised compliance. The only products willing to un dergo our scrutiny were BorderWare and Sidewinder. Since both products are from Secure Computing, we were optimistic about setting up an IPsec VPN between them. Unfortunately, our optimism was premature. Although we were assured that IPsec-standard VPNs worked great when using only BorderWare or only Sidewinder, we discovered that even when using manual key management, IPsec VPNs between firewalls just isn't there yet, even for products from the same company.

Make Room for Frame Relay by David Willis Updated Februayr 7, 1997