Firewall

Firewall:

A Firewall is a software program which prevents outside network entering to an intranet.

Basic firewall task are:

• Defend network resource
  
• give access to authorized network
  
• manage the follow of network traffic
  
• Record and report an network event
  
• and respond quick on any mishaps in network
  

for a group of users Software firewall is enough. But for larger network a hareware firewall is required,
Windows has a build in firewall called Windows Defender, for Linux there is build in package called Firewalld.