Firewall

Firewall is a network security device protects the application layer against attempted fraud or data theft; blocking suspicious activity. Inspecting every web request for cross-site scripting, SQL injection, this protective layer ensures that your data remains secure, a firewall is essentially the barrier that sits between a private internal network and the public Internet.

Firewall: Stateful Packet Inspection . In this learning activity you'll examine a stateful packet inspection firewall that keeps track of legitimate Internet service requests, also known as dynamic packet filtering.

Firewalls: Packet Filters. In this learning activity you'll create a packet filter.

Firewall: Gateway Servers. In this animated object, learners examine how a gateway server operates.

Firewall: Network Address Translation/Port Address Translation. In this learning activity you'll examine how network address translation works.

Firewalls: Relationships Among Firewall Perimeters. In this learning activity you'll examine how firewalls block viruses by discussing trusted, semi-trusted, and untrusted networks.