Cyclades User's Guide manual Rule

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Table 1-15:Levels of IP Filtering (Continued)

Rule

Each chain contains a sequence of rules that control filtering. The rules address the following issues:

•How the packet should appear in order to match the rule

Some information about the packet is checked according to the rule, for example, the IP header, the input and output interfaces, the TCP flags and the protocol.

•What to do when the packet matches the rule

The packet can be accepted, blocked, logged, or jumped to a user-defined chain.

When a chain is analyzed, the rules of this chain are reviewed one-by-one until the packet matches one rule. If no rule is found, the default action for that chain will be taken.

Introduction 39