What is a network firewall?
A firewall is a system or group of systems that enforces an access-control policy between two networks. It may also be defined as a mechanism used to protect a trusted network from an un-trusted network. The firewall can be thought of two mechanisms. One to block the traffic, and the other to permit traffic.
A firewall is a system or group of systems that enforces an access control policy between two or more networks. The actual means by which this is accomplished varies widely, but in principle, the firewall can be thought of as a pair of mechanisms: one which exists to block traffic, and the other which exists to permit traffic. Some firewalls place a greater emphasis on blocking traffic, while others emphasize permitting traffic. Probably the most important thing to recognize about a firewall is that it implements an access control policy. If you don’t have a good idea of what kind of access you want to allow or to deny, a firewall really won’t help you. It’s also important to recognize that the firewall’s configuration, because it is a mechanism for enforcing policy, imposes its policy on everything behind it. Administrators for firewalls managing the connectivity for a large number of hosts therefore have a heavy responsibility.
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. 2.2 Why would I want a firewall? The main objective of a firewall is to protect your network from jerks without hampering your work. There are users who use Internet for getting real work done; however, there are many who try to capture sensitive information from other people’s mailboxes. Almost all the organizations and data centers have a set of computing security policies and practices to follow. Consider an example, w
A firewall is a system or group of systems that enforces an access control policy between two networks. The actual means by which this is accomplished varies widely, but in principle, the firewall can be thought of as a pair of mechanisms: one which exists to block traffic, and the other which exists to permit traffic. Some firewalls place a greater emphasis on blocking traffic, while others emphasize permitting traffic. Probably the most important thing to recognize about a firewall is that it implements an access control policy. If you don’t have a good idea what kind of access you want to permit or deny, or you simply permit someone or some product to configure a firewall based on what they or it think it should do, then they are making policy for your organization as a whole.
A firewall is a system or group of systems that enforces an access control policy between two networks. The actual means by which this is accomplished varies widely, but in principle, the firewall can be thought of as a pair of mechanisms: one which exists to block traffic, and the other which exists to permit traffic. Some firewalls place a greater emphasis on blocking traffic, while others emphasize permitting traffic. Probably the most important thing to recognize about a firewall is that it implements an access control policy. If you don’t have a good idea of what kind of access you want to allow or to deny, a firewall really won’t help you. It’s also important to recognize that the firewall’s configuration, because it is a mechanism for enforcing policy, imposes its policy on everything behind it. Administrators for firewalls managing the connectivity for a large number of hosts therefore have a heavy responsibility.
