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EES4710BD 10 Slots L2/L3/L4 Chassis Switch
added to the switch MAC table.
2. At the same time, the switch learns the message is destined to 00-01-33-33-33-33, as the MAC
table contains only a mapping entry of MAC address 00-01-11-11-11-11 and port 1/5, and no
port mapping for 00-01-33-33-33-33 present, the switch broadcasts this message to all the ports
in the switch (assuming all ports belong to the default VLAN).
3. PC3 and PC4 on port 1/12 receive the message sent by PC1. PC4 will not reply, as the
destination MAC address is 00-01-33-33-33-33 Only PC3 will reply to PC1. When port 1/12
receives the message sent by PC3, a mapping entry for MAC address 00-01-33-33-33-33 and
port 1/12 is added to the MAC table.
4. Now the MAC table has two dynamic entries, MAC address 00-01-11-11-11-11, port 1/5 and
00-01-33-33-33-33, port 1/12.
5. After the communication between PC1 and PC3, the switch does not receive any messages sent
from PC1 and PC3. And the MAC address mapping entries in the MAC table are deleted after
300 seconds. The 300 seconds here is the default aging time for MAC address entry in
ES4710BD. Aging time can be modified in ES4710BD.
8.1.2 Forward or Filter
The switch will forward or filter received data frames according to the MAC table. Take the
above figure as an example, assuming ES4710BD has learnt the MAC address of PC1 and PC3, and
the user manually configured the mapping relationship for PC2 and PC4 to ports. The MAC table of
ES4710BD would be:
MAC Address Port number Entry added by
00-01-11-11-11-11 1/5 Dynamic learning
00-01-22-22-22-22 1/5 Static configuration
00-01-33-33-33-33 1/12 Dynamic learning
00-01-44-44-44-44 1/12 Static configuration
1. Forward data according to the MAC table
If PC1 sends a message to PC3, the switch will forward the data received on port 1/5 to port 1/12.
2. Filter data according to the MAC table
If PC1 sends a message to PC2, the switch, on checking the MAC table, will find PC2 and PC1 are
in the same physical segment and filter the message (i.e., drop this message).
Three types of frames can be forwarded by the switch:
Broadcast frame
Multicast frame
Unicast frame
The following describes how the switch deals with all the three types of frames:
1. Broadcast frames: The switch can segregate collision domains but not broadcast domains. If no
VLAN has been set, all devices connected to the switch are in the same broadcast domain.
When the switch receives a broadcast frame, it forwards the frame to all ports. When VLANs