ZyXEL Communications Prestige 128L, Руководство пользователя

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76 Filter Configuration
1. Offset - Offset refers to the value of the byte that you want to use
as your starting offset. That is, in the data packet, at what point do
you want to begin the comparison. The range for this field is from 0
to 255.
Default = 0
2. Length - This field refers to the length (in bytes) of the data in the
packet that your Prestige should use for comparison and masking.
The starting point of this data is determined by Offset. The range for
this field is 0 to 8.
Default = 0
3. Mask - In this field, specify (in Hexadecimal) the value that your
Prestige should logically qualify [and] the data in the packet. Since
Length is given in bytes, you need to enter in twice the length
hexadecimal numbers for this field. For example, if Length were 4,
then a valid Mask must have 8 hexadecimal numbers, like
1155ABF8.
4. Value - In this field, specify (in Hexadecimal) the value that your
Prestige should use to compare with the masked packet. The value
should align with Offset. Since Length is given in bytes, you need to
enter in twice the length hexadecimal numbers for this field. For
example, if Length were 4, then a valid Value must have 8
hexadecimal numbers, like 1155ABF8. If the result from the
masked packet matches Value, then the packet is considered
matched.
Once you have completed filling in Menu 21.1.1 - Generic Filter Rule,
press
ENTER at the message: Press ENTER to Confirm ... to confirm
your selections, or press ESC at any time to cancel your selections.
This data will now be displayed on Menu 21.1 - Filter Rules Summary.