List four technique used by firewalls to control access and enforce a security policy?

Answer 1

Techniques used by firewall:

There are four general techniques that firewall use to control access and enforce the sites security policy:

• Service Control:

  Determines the types of internet services that can be accessed, inbound or outbound.

  Firewall may filter traffic on the basis of IP address and TCP port number.

  It may provide proxy software that receives and interprets each service request before passing it on.

  It may host the server software itself such as a web or mail service.

• Direction control:

  Determines the direction in which particular service request may be initiated and allowed to flow through firewall.

• User control:

  Control access to a service according to which user is attempting to access it. This feature is applied to users inside the firewall perimeter. It may also be applied to incoming traffic from external users. But it requires some form of secure authentication technology.

• Behavior control:

  Controls how particular services are used. For eg.the firewall may filter email to eliminate spam or it may enable external access to only a portion of the information on a Local web server.