Mac Address Table Configuration Command List; Mac-Address-Table Aging-Time - Digitalchina Networks DCS-3950 series Manual

If PC1 sends a message to PC3, the switch will forward the data received on port 5
from port 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 frame: The switch can segregate collision domains but not broadcast
domains. If no VLAN is set, all devices connected to the switch are in the same
broadcast domain. When the switch receives a broadcast frame, it forwards the frame
in all ports. When VLANs are configured in the switch, the MAC table will be adapted
accordingly to add VLAN information. In this case, the switch will not forward the
received broadcast frames in all ports, but forward the frames in all ports in the same
VLAN.
2. Multicast frame: When IGMP Snooping function is not enabled, multicast frames are
processed in the same way as broadcast frames; when IGMP Snooping is enabled,
the switch will only forward the multicast frames to the ports belonging to the very
multicast group.
3. Unicast frame: When no VLAN is configured, if the destination MAC addresses are in
the switch MAC table, the switch will directly forward the frames to the associated
ports; when the destination MAC address in a unicast frame is not found in the MAC
table, the switch will broadcast the unicast frame. When VLANs are configured, the
switch will forward unicast frame within the same VLAN. If the destination MAC
address is found in the MAC table but belonging to different VLANs, the switch can
only broadcast the unicast frame in the VLAN it belongs to.

8.2 MAC address table configuration Command List

8.2.1 mac-address-table aging-time

Command：mac-address-table aging-time {<age>| 0}
no mac-address-table aging-time
Function: Set the aging time for address mapping entries in the MAC table dynamically
learnt; the 'no mac-address-table aging-time' command restores the aging time to the
default 300 seconds.
DCS-3950 series Ethernet switch manual
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