ZyXEL Communications Prestige 100, Руководство пользователя

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86 Filter Configuration
Figure 8-5 Menu 21.1.1 - Generic Filter Rule
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 the 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 the
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
the 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