A Comparison of Firewalls

A firewall and its purpose

A firewall is a network security system which functions by filtering outgoing and incoming traffic network based on the user-defined laws. Its purpose generally is to eliminate and reduce the entry of unwanted network communication. Network administrators prefer to accurately know which ports are responding to particular software so that they can use the relevant firewall ports to defend the network from malicious attacks (Ahmad, Khandoker, and Nawrin 10). Network protection requires knowledge of where an attack emanates. For instance, if the network, through the firewall, is not anticipating traffic on port 697, and one assumes or refuse all traffic requests on such a port, an attacker cannot access the site for their dirty work.

Networks using PAT

It is apparent that most of the networks use PAT. In this regard, the ISP assigns one IP address to the designated router. For example, if computer 'A' logs on to the internet using the already assigned router, the router assigns the individual that has logged on with a port number attached to the inbuilt IP address (Tipton and Krause 342). Thus, computer A is given a unique address. In this case, if computer 'B' logs on simultaneously, the router assigns it the same IP address but with a different port number (Suehring 35). Hence, this may pose a threat to attackers who would use the IP address to obtain information from all those computers using the same internet source.

Using random numbers in proxy firewalls

However, the administrator can use the random numbers in case it was a proxy firewall. This is because unlike other firewalls, the data does not pass through the proxy, but rather functions as an intermediary where the network connection request if first sent, then the information is checked before the connection is allowed.

Works Cited

Ahmad, Syed Jamaluddin, Roksana Khandoker, and Farzana Nawrin. "Security Enhancement & Solution for Authentication in Corporate Network with Firewall Configuration and Authentication for Server Protocol." GSJ 6.5 (2018): 10.

Suehring, Steve. Linux firewalls: Enhancing security with Nftables and beyond. Addison-Wesley Professional, 2015.

Tipton, Harold and Krause Micki. Information Security Management Handbook. New York: CRC Press, 2003. Print