What it is, How it works

A: A firewall is a collection of hardware and software components that are placed between two networks for security, often between a private network and the Internet. Typically, a firewall has the following properties:

• All traffic from inside to outside, and vice-versa, must pass through the firewall
• Only authorized traffic, as defined by local security policy, is allowed to pass the firewall
• All traffic, whether allowed to pass or rejected, must be logged for audit purposes and scanned for possible trouble
• The firewall removes features that are of doubtful security, and is immune to penetration.

A: A firewall protects the systems and data on your network, while still letting you get your job done. In a case where a company's security policies dictate how data must be protected, a firewall is very important since it embodies corporate policy. A firewall can act as your corporate "ambassador" to the Internet. Many corporations use their firewall systems as a place to store files to download, bug-fixes, public information about corporate products and services, and more.

Q: What can a firewall protect against?

A: Generally, firewalls are configured to protect against unauthenticated interactive log-ins from the "outside" world. Firewalls, more than any other function, help prevent vandals from logging into machines on your network. Some firewalls permit only e-mail traffic through them. Others provide less strict protection, and block services that are known to be problems. More elaborate firewalls block traffic from the outside to the inside, but permit users on the inside to communicate freely with the outside.

Firewalls are also important since they can provide a single point where security and auditing can be imposed.

Q: What can't a firewall protect against?

A: Firewalls cannot protect against attacks that don't go through the firewall. For example, a magnetic tape can just as effectively be used to export data as a network. Allowing physical access to your firewall console is also extreme risky.

Although separate software can be run on the firewall for virus detection, firewalls cannot offer complete protection against viruses entering via the desktop. Nor can a firewall protect against a data-driven attack, in which a file is mailed or copied to an internal host, where its hidden code is then executed.

Q: Is AltaVista's Firewall NCSA Certified?

A: Yes! All AltaVista Firewalls have received the NCSA Firewall Certification. In fact, AltaVista Firewall for Windows NT is the world's first firewall to receive the NCSA certification.

Q: What makes AltaVista Firewall different from other firewalls?

A: AltaVista Firewall deploys a unique combination of technologies that enable you to place a highly-secure, yet flexible barrier among your private networks, the Internet, and other private networks. AltaVista Firewall combines trusted application gateways for popular Internet services with real-time reporting, comprehensive logging, custom reporting, evasive action, anti-spoofing, strong user authentication, and an industry-leading graphical user interface (GUI), to provide you with an unparalleled level of protection.

Q: Is the AltaVista Firewall software easy to work with?

A: Yes! AltaVista Firewall hides the complexity of configuration and management behind an easy-to-use, menu-driven graphical user interface (GUI). If you can point-and-click, you can set up AltaVista Firewall - it's that easy! All configuration tasks are performed through the GUI, which implements rigorous error-checking on all settings, making sure your settings are correct and your network is secure.

Network World magazine, in a review of firewalls published in January 1996, stated: "Digital's Firewall for UNIX has the best thought-out and most powerful management interface of all the products we examined. If you want a firewall but don't want to play with UNIX, you should definitely investigate Digital's Firewall for UNIX. The best management interface of all the firewalls we looked at makes this product easy to configure and use."

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