Introduction to Filtering

The following operators are used in creating Pattern filters.

 

 

-

offset

Used

in pattern filters

 

to determine

the starting

 

 

position to start the pattern checking.

 

 

 

Example:

12-80

This filter pattern will match

 

 

 

 

if

the

packet

information

 

 

 

 

starting at the 12th

octet

 

 

 

 

equals the 80 of the filter

 

 

 

 

pattern.

 

 

 

OR

Used in combination filters when one or the other

 

 

conditions must be met.

 

 

 

 

 

 

Example:

10-2012-80

This filter pattern will match

 

 

 

 

if

the

packet

information

 

 

 

 

starting at the 10th

octet

 

 

 

 

equals the 20 of the filter

 

 

 

 

pattern or if the packet

 

 

 

 

information starting

at the

 

 

 

 

12th octet equals the 80 of

 

 

 

 

the filter pattern.

 

 

&

AND

Used in combination filters when one and the other

 

 

conditions must be met.

 

 

 

 

 

 

Example:

10-20&12-80

This filter pattern will match

 

 

 

 

if

the

packet

information

 

 

 

 

starting at the 10th

octet

 

 

 

 

equals the 20 of the filter

 

 

 

 

pattern

and

the

packet

 

 

 

 

information starting

at the

 

 

 

 

12th octet equals the 80 of

 

 

 

 

the filter pattern.

 

 

~

NOT

Used in pattern filters to indicate that all packets not

 

 

matching the defined pattern will be filtered.

 

 

Example:

~12-80

This filter pattern will match

 

 

 

 

if

the

packet

information

 

 

 

 

starting at the 12th octet

 

 

 

 

does not equal the 80 of the

 

 

 

 

filter pattern.

 

 

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Black Box LR1530A-EU-R3, LR1530A-R3 manual Not