Firewalls

A firewall is a device which creates a barrier to network traffic, separating a network into a trusted zone and an untrusted zone. A firewall is designed to allow traffic from the untrusted zone to enter the trusted zone only in certain circumstances. This protects computers in the trusted zone from:

• Hackers
• Worms (Viruses)
• Other users with malicious intent

Most modern operating systems include a built-in firewall. However, in order to work properly on Resnet, the firewall on your computer must be configured properly.

Firewalls supported by Resnet Support

Resnet staff are able to provide support for firewalls provided by several different vendors. It is important to note that this list is not comprehensive, as our more experienced staffmembers may be familiar with more products than are on this list.

• Windows Firewall (included in Windows XP and Windows Vista)
• Mac OS X Firewall
• Norton Firewalls
• McAffee Firewalls
• ZoneAlarm Firewall

If your firewall is not on this list, it does not mean that it is incompatible with Resnet. It does mean, however, that it may take our staff longer to provide support for your product.

Configuring a Firewall for use on Resnet

In order for Resnet's servers to identify a computer on the network, the computer must respond to what are called ICMP Echo Request packets. By default, many firewalls block this kind of packet, because some internet worms will use this protocol to identify potential targets. On Resnet, allowing this type of packet presents no security risk.