Chapter 3 — AsantéBridge 1012 Local Management
When a device on either segment transmits, its packets are read by the bridge.The bridge reads the source address contained in the packets and writes that address into the table as a dynamic entry with a tag associating it with the segment it was received on.Thereafter, when the bridge receives a packet on either seg- ment, it will compare the destination address of that packet to the table entry.
If there is a match, the packet is forwarded to the appropriate seg- ment. If there is no match, the packet is forwarded to the oppo- site segment from which it is received.
Static table entries are treated differently.These are manually entered and are only deleted from the table under circumstances defined at the time the addresses are entered.There are also differ- ences in the way the bridge treats these entries.
When the bridge receives a packet from either segment, it reads the destination address of the packet and checks the forwarding table for static entries. If a match is found, the packet is forwarded according to the instructions associated with the matching table entry.
If a match is not found in the static entries, the table is checked again to see if there is a dynamic entry for this address.
If there is already a dynamic entry the bridge then checks for a dynamic entry matching the destination address of the packet and forwards it accordingly.
If there is no existing dynamic entry, the bridge writes the source address into the table as a dynamic address as described above.
In summary:
❏A dynamic entry is derived from the source address of an incoming packet and is used to direct forwarding of packets carrying this address as their destination address.
❏A static entry is manually entered and is used to direct forwarding of packets carrying this address as their des- tination.
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