PLANET XGS3-24042 - Manual (Page 148)

16-3
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:
 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.
 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.
 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.
16.2 Mac Address Table Configuration Task List
1. Configure the MAC address aging-time
2. Configure static MAC forwarding or filter entry
3. Clear dynamic address table
1. Configure the MAC aging-time
Command Explanation
Global Mode
mac-address-table aging-time
<0|aging-time>
no mac-address-table aging-time
Configure the MAC address aging-time.
2. Configure static MAC forwarding or filter entry
Command Explanation
Global Mode
mac-address-table {static | blackhole}
address <mac-addr> vlan <vlan-id >
[interface [ethernet | portchannel]
Configure static MAC forwarding or filter
entry.