What are Firewalls?
"A firewall is a network security system, either hardware or software-based, that uses rules to control incoming and outgoing network traffic." (1).
A firewall is very similar to a barrier the defends your network from incoming and outgoing malicious signals. It determines if the drawbridge should be let down.
Only specific data can be sent through the wall and all other information is denied. There are four types of firewalls, Packet, Stateful, Application-layer, and Proxy (1).
Packet firewalls and programmable filters that allow and deny packets (information) from being sent and received from your computer.
The destination address, protocol, and destination port number are all checked before your computer can receive the information. Packet firewalls can be
programmed to stop signals from a specific port (1).
Stateful firewalls conduct a "stateful packet inspection." to record where packets are being sent from and received. If a packet has been verified previously then
it will be sent to somebody's computer way quicker then a random program that has never been seen (1).
Application-layer firewalls blocks previously identified malware from online sites and information. It has the ability to block specific malware content (1).
Proxy firewalls identifie a connection from two devices and can block or allow both sides to connect. This is determined by a predefined rule set embedded in the
programming (1).
