Firewall Software is consist of programs specifically designed in monitoring and
controlling the activity of traffic between networks and computers. Firewalls are
commonly used to avoid the unofficial access both on computers and networks.
Generally speaking, firewall software can allow, restrict, encrypt or proxy computer
traffic. It is an effective tool to be able to keep the sense of confidentiality of the pc.
Unauthorized parties are not allowed to access confidential file.
Originally, Firewall is referred to a wall that is used as safety net to be able to confine
threats. The first known firewall is Packet filters wherein it is mostly involve in
technical internet security feature. It has the ability to inspect the “packets” that are
transferred between several computers. Once the packet matches that filter set of rules,
it will be discarded silently or reject it. It filters based on the information attached in the
packet itself. Next is Stateful Filters in which it works similarly to packet filter, however
it can operate up to the 4th layer of OSI model. It is commonly done by maintaining
packets until what is left is the available for judgment about its state. It has the ability
to record and monitor all connection that passes through. The third one is Application
layer has the ability to understand specific applications and protocols such as FTP, DNS
or HTTP. This is an effective tool in detecting and preventing unwanted protocol that
might get through the firewall on the allowed port of firewall.