Question

A ............ protects a computer from unauthorized access, by blocking all unnecessary network ports, which prevents a network program from communicating with another computer.

Q: Answer-A ............ protects a computer from unauthorized access, by blocking all unnecessary network...

A firewall is a network security system, either hardware- or software-based, that uses rules to control incoming and outgoing network traffic. A firewall acts as a barrier between a trusted network and an untrusted network. A firewall controls access to the resources of a network through a positive control model. This means that the only traffic allowed onto the network is defined in the firewall policy all other traffic is denied.