Firewalls are always used for network perimeter security in most of the organizations, firewalls are always considered a robust device for defence in network security. The cisco ASA is one of the earlier used firewall and many of the companies still use it for their network infrastructure security.Cisco ASA Firewall is one of the proven best in industry firewall. Cisco ASA provides a combined firewall, NAT, SSL VPN, antivirus, intrusion prevention, and virtual private network (VPN) capabilities. It provides proactive threat defense that also which stops attacks before they spread through the network.