Obtaining Mac Table - Accton Technology ES4710BD User Manual

period. When the switch receives a data frame to be forwarded, it stores the source MAC address of
the data frame and creates a mapping to the destination port. Then, the MAC table is queried for the
destination MAC address, if hit, the data frame is forwarded to the associated port, otherwise, the
switch forwards the data frame to its broadcast domain. If a dynamic MAC address is not learnt
from the data frames to be forwarded for a long time, the entry will be deleted from the switch's
MAC table.
There are two MAC table operations:
1. Obtain a MAC address
2. Forward or filter data frame according to the MAC table
8.1.1

Obtaining MAC Table

The MAC table can be built by static configuration and dynamic learning. Static configuration
sets up a mapping between the MAC addresses and the ports, Dynamic learning is the process in
which the switch learns the mapping between MAC addresses and ports, and updates the MAC table
regularly. In this section, we will focus on the dynamic learning process of MAC table.
PC1
MAC 00-01-11-11-11-11
The topology of the figure above: 4 PCs connected to ES4710BD, where PC1 and PC2 belong
to a same physical segment (same collision domain), the physical segment connects to port 1/5 of
ES4710BD; PC3 and PC4 belong to the same physical segment that connects to port 1/12 of
ES4710BD.
The initial MAC table contains no entries. Take the communication of PC1 and PC3 as an
example, the MAC address learning process is as follows:
1. When PC1 is sending a message to PC3, the switch receives the source MAC address
00-01-11-11-11-11 for this message, the mapping entry of 00-01-11-11-11-11 and port 1/5 is
EES4710BD 10 Slots L2/L3/L4 Chassis Switch
1/ 5
PC2
MAC 00-01-22-22-22-22
Fig 8-1 MAC Table dynamic learning
181
1/ 12
PC3
MAC 00-01-33-33-33-33
PC4
MAC 00-01-44-44-44-44