SPRUIV7B May 2022 – September 2023 AM620-Q1 , AM623 , AM625 , AM625-Q1 , AM625SIP
The 3-port switch has a host port, and that port can operate in two fundamental modes. Bridge mode allows the host to extent the switched domain to another network like Wi-Fi or another multi-port switch. In this case the host must be able to see unknown unicast addresses so they can be broadcast to the other network. In Port mode the host need not see any unknown unicast traffic. The CPSW_ALE_CONTROL[8] EN_HOST_UNI_FLOOD bit determines the host mode for unknown unicast traffic. This bit should only be set if the user is bridging two or more networks together.
The 3-port switch can operate like a two-port switch using the ALE table just for the host info, the only adder is now other VLANs need to be supported for transit traffic between the external ports. This can easily be done using the default VLAN rules so no ALE table entries are used.
The 3-port switch can also operate in a fully authenticated environment where all network nodes are registered via the 802.1x based protocols. In this case the ALE table is filled with network node addresses that have been authenticated