Black Box LR1530A-EU-R3 - Manual (Page 66)

Introduction to Filtering
60
( ) brackets Used in pattern filters to separate portions of filter
patterns for specific operators.
Example: 12-80&(14-24|14-32) This filter pattern will be
checked in two operations.
First the section in brackets
will be checked and then the
results of the first check will
be used in the second check
using the first portion of the
filter pattern. If the packet
information starting at the
14 th octet equals 24 or 32,
and the information at the
12 th octet equals 80, the filter
pattern will match.