What is a network firewall?
A system or group of systems, which imposes an access control policy between two or more networks, is termed as firewall. In simple words, firewall is a method or mechanism to block and allow traffic. Certain firewalls block traffic while others allow traffic. However, it is essential that you have a clear idea about what kind of access has to be allowed and what has to be denied. You should also understand about the configuration and the mechanism to enforce firewall. Firewall administrators have to manage large amount of hosts and hence it is a great responsibility.
