Filter Expressions

This section specifies the syntax and semantics for defining filter expressions.

The syntax for the filter expressions is shown below.

<FilterExpressionSpec>  ::= <FilterExpression> | ( '(' <FilterExpressionSpec> [ <FilterOperator> <FilterExpressionSpec> ] ')' )
<FilterExpression>      ::= 'All' | <ProtocolTest> | <DataTest> | <IPMatchTest> |
                            <LengthTest> | <ErrorTest> | <PortTest> |
                            <KeyMatchTest> | <KeyTest>
<FilterOperator>        ::= 'AND' | 'OR'

A filter expression consists of one or more tests combined using one or more filter operators ('AND' and/or 'OR'). The tests can be:

• Protocol Tests
• Data Tests
• IP Match Tests
• Length Tests
• Error Tests
• Port Tests
• Key Match Tests
• Key Tests