What is PIX firewall security? How does it differ from a firewall?

PIX (Private Internet Exchange)

It is a popular IP firewall and NAT (Network Address Translation) appliance. 

 PIX firewall security is developed by Cisco Systems. 

 PIX firewall is used to protect your network with a stateful packet filtering firewall. 

 A firewall is a part of a computer system or network that is designed to block unauthorized access while permitting authorized communications.