Firewall and Firewall Security Techniques
A firewall can be described as a security network system that monitors and controls the network traffic based on pre-determined security rules (Stewart, 2013). It can also be termed as a barrier between an internal network, which is a trusted and external untrusted network. A firewall acts as an intermediary that protects the system from connecting directly to an untrusted network. The Firewall uses filtering techniques to protect the computer or system from harm and threats by using several methods, which include packet filter, gateway application, and circuit-level gateway, and proxy server.
Gateway application installs security operations to specific applications. The technique can cause performance degradation, but it is said to be very useful. All messages getting in or out of the network are intercepted by the proxy server (Stewart, 2013). It effectively hides exact network addresses, and intruders are unable to obtain the addresses. Level circuit gateway applies security operations when transmission control protocol and data protocol connection is developed. Packet filter filters each packet leaving or entering the network by rejecting or accepting it based on the set rules. Packet filters are quite transparent and effective but difficult in configuring. Packet filters easily fall victim to IP spoofing allowing intruders to send messages to the computer with an IP address indicating the messages are coming from a trusted host.
References
Stewart, J. M. (2013). Network Security, Firewalls, and VPNs. Sudbury: Jones & Bartlett Learning, LLC.