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Mask Bytes
As an alternative to placing wildcards (00) in the MAC Address field, the Mask Bytes column allows you to select which octets in the MAC Address field will be read by the CPU (see Figure 37).
Entering ff into a mask bytes octet instructs the CPU to allow only MAC octets with a value matching the same location in the MAC Address field to pass. The CPU rejects any other entry in the octet position.
Entering a 00 into a mask bytes octet instructs the CPU to “mask” the octet. When the octet is masked, the CPU allows any entry to pass.
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Byte Position: 1 2 3 4 5 6
MAC Address: 00 A0 D4 00 00 00
Mask Bytes: ff ff ff 00 00 00
ff= the byte in this position must match 00 = allow any digit in this section
Figure 37: Working with Mask Bytes
Entering an ff into a mask bytes octet, and a 00 in the same octet position of the MAC Address instructs the CPU to allow an entry matching only 00 to pass.
Source/Dest.
The Source/Dest. column allows you to specify whether the action upon packets will occur if that node is sending or receiving packets.
| Page 59 | © 1999 RadioLAN, Inc. |