Saturday, May 10, 2014

CAM Table Operation

Non-VLAN-Capable Switch CAM Table Operation
A Switch uses its CAM (Content addressable memory) table to store MAC addresses and the associated port where each MAC address was learned. Once the Switch receives a frame, it uses its CAM table in order to determine what to do with the frame.

1.     If the destination MAC address is not appearing in the CAM table, then the Switch sends (Flood) the frame to all ports except for the port through which it arrived.
2.     If the destination MAC address appears in the CAM table, then the frame is sent to the identified port for transmission. (Forward)
3.     If the destination MAC address comes from the same port on which it was received, it is discarded. (Filter)
4.     If the destination MAC address is a broadcast or multicast address, then the frame is sent to all ports, excluding the received port. (Flood)

VLAN-Capable Switch CAM Table Operation
A Switch uses its CAM table to store MAC addresses and the associated port and the port VLAN ID where each MAC address was learned. Once the Switch receives a frame, it uses its CAM table to determine which action to take.

1.     If the destination MAC address is not appearing in the CAM table, then the Switch sends (Flood) the frame to all ports with matching VLAN ID, excluding the received port.
2.     If the destination MAC address appears in the CAM table, then the frame is sent (Forward) to the port with matching VLAN ID for transmissions.
3.     If the destination MAC address comes from the same port on which it was received, it is discarded. (Filter)
4.     If the destination MAC address is a broadcast or multicast address, then the frame is sent (Flood) to all ports with matching VLAN ID, excluding the received port.


No comments:

Post a Comment