A firewall is a part of a computer system or network that is designed to block unauthorized access while permitting authorized communications. It is a device or set of devices which is configured to permit or deny computer applications based upon a set of rules and other criteria.
Firewalls can be implemented in either hardware or software, or a combination of both.
In windows 2003 server, built in firewall is present
To enable firewall in Window...Start - Control panel - Security center -Turn On the Firewall Button and enable it. ...
A firewall system in which service is provided by processes that maintain complete TCP connection state and sequencing. Application layer firewalls often re-address traffic so that outgoing traffic appears to have originated from the firewall, rather than the internal host.
The process of determining what types of activities are permitted. Usually, authorization is in the context of authentication: once you have authenticated a user, they may be authorized different types of access or activity.
A router configured to permit or deny traffic based on a set of permission rules installed by the administrator.
A software agent that acts on behalf of a user. Typical proxies accept a connection from a user, make a decision as to whether or not the user or client IP address is permitted to use the proxy, perhaps does additional authentication, and then completes a connection on behalf of the user to a remote destination.
The process of storing information about events that occurred on the firewall or network.
Depend on firewall configuration, all most authorize port nb 80, so we can communicate over Http protocol. ...