12.1 list three design goals for a firewall.
12.2 list four techniques used by firewalls to control access and enforce a security policy.
12.3 what information is used by a typical packet filtering firewall?
12.4 what are some weaknesses of a packet filtering firewall?
12.5 what is the difference between a packet filtering firewall and a stateful inspection firewall?
12.6 what is an application-level gateway?
12.7 what is a circuit-level gateway?
12.9 what are the common characteristics of a bastion host?
12.10 why is it useful to have host-based firewalls?
12.11 what is a dmz network and what types of systems would you expect to find on such networks?
12.12 what is the difference between an internal and an external firewall?

Firewall:

There are 2 type of firewall

1. Firewall which is installed with antivirus on desktop or laptop is called resident firewall, where protects end user desktop or laptop from malware and spyware attacks.

2.  Physical hardware appliances which is install in in local area network and protect us from malware and spyware attack’s

12.1  1. Access point (AP) bridge Ethernet network.

       2. Protect wireless access or unauthorized person.

       3. Web shared key.

12.2  1. User controls

        2. Direction control

        3. behaviour control and

        4. HTTP REQUESTS.

12.3 Source tcpip, destination tcpip

12.4 Complex configures unauthorized use, suspicious tcpip, protocols attacks and logging capacities limitations.

12.5 State inspection firewall stable connectivity for open connection. Whereas a packet filter will not do that.

12.6 Application gateways is proxy firewall provides network security

12.7 In circuit-level gateway it works as session layers in tcpip traffic.

12.9 It filters incoming traffics from mall ware and anti-spams.

12.10 To protect against threats in the corporate networks.

12.11. All access to resources from untrusted networks

12.12 Protect or permitted traffic inside networks - internal networks.  Protect or block traffic at port level – external networks.