General Firewall Troubleshooting
If you received an error message about a firewall, or if you are not sure whether a firewall is
preventing you from accessing this site's content, find out by asking your Network
System Administrator or your Internet Service Provider.
Firewall: A firewall is a system designed to prevent unauthorized access
to or from a private network. Firewalls can be implemented in both hardware and software,
or a combination of both. Firewalls are frequently used to prevent unauthorized Internet
users from crossing private networks connected to the Internet, especially intranets.
All messages entering or leaving the intranet pass through the firewall,
which examines each message and blocks those that do not meet the specified
security criteria. A firewall is considered a first line of defense in protecting
private information.