In the world of computer firewall protection, a firewall refers to a network device which blocks certain kinds of network traffic, forming a barrier between a trusted and an untrusted network. It is analogous to a physical firewall in the sense that firewall security attempts to block the spread of computer attacks.

A Hardware Firewall is a device or set of devices used to protect individual computers or a network of computers from the threat of information or data leakage. It acts by filtering out requests from unauthorized users to access data. Finally, despite all the resources spent and a dedicated team in charge, we still keep hearing about incidents of huge data leakages from major corporates. This can only be prevented by constant vigilance, up-gradation and monitoring of the systems without any complacency.

Software firewalls are installed on individual computers on a network. Unlike hardware firewalls, software firewalls can easily distinguish between programs on a computer. This lets them allow data to one program while blocking another. Software firewalls can also filter outgoing data, as well as remote responses to outgoing requests. The major downside to software firewalls for a business is their upkeep: they require installation, updating and administration on each individual computer.