Microsoft Technology Licensing, LLC

Avihai Lifschitz

Yosef Dinerstein

Amit Finkelstein

Ziv Caspi

A generic master-slave mechanism enables a single processor of a cluster of firewall processors to define the behavior of the other processors in the cluster for a specific logical connection. The cluster of firewall processors utilizes virtual adapters representing physical adapters on other processors in the firewall cluster. This virtualization allows each cluster member to act as though it is a standalone machine that owns all local IP addresses of the entire cluster. When traffic is received by a firewall processor, the firewall processor determines if there is a master associated with the logical connection for the traffic. If so, the traffic is routed to the master. If no master is associated, in an example configuration, the receiving firewall processor becomes the master. A message traffic logical connection has a single master. A master remains the master of a logical connection until the connection is terminated.

Transparently extensible firewall cluster

The evaluation of a policy can be delayed until all rules criteria needed for evaluation are available. Also, new types of rules criteria can be registered without requiring changes to a rules engine. A policy manager allows rules to be evaluated and decisions made at different stages of the request handling. The policy manager facilitates interaction with the rules engine until all criteria are evaluated. The policy manager also allows modules developed by third parties to provide notification when criteria can be decided and thus complete evaluation.

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Bellevue, WA, United States of America

Avihai Lifschitz