Method and apparatus for updating provider domain due to customer TCNs

A method for communication between two or more customer local area network (LAN) segments through a provider network, where each customer LAN segment including a customer edge bridge, and where the provider network has one or more provider edge bridges coupled to the customer edge bridges, comprising the steps of:

• in each edge bridge of a LAN segment having a multi-homed connection to the provider network:
• flagging topology change notifications (TCNs) which relate to topology changes affecting paths of data units through the provider network;
• and
• in each of the provider edge bridges coupled to a customer LAN segment:
• receiving topology change notifications (TCNs) from the customer network;
• in response to receiving a flagged TCN, flushing an address memory file associating end host addresses with ports of the provider edge bridge;
• and
• in response to receiving an unflagged TCN, passing the TCN without flushing an address memory file.

A provider edge bridge of a provider network for providing communication with one or more customer edge bridges of customer local area network (LAN) segments, comprising:

• processing circuitry for:
• receiving topology change notifications (TCNs) from the oen or more customer bridges;
• in response to receiving a TCN, monitoring end host addresses in data units received from the one or more customer bridges for a predetermined time period;
• flushing an address memory file associating end host addresses with ports of the provider edge bridge if a data unit received in the predetermined time period has a end host address indicating that a topology change has occurred in one or more of the customer LAN segments affecting paths of data units through the provider network.

A communication network including two or more customer local area network (LAN) segments coupled through a provider network, where each customer LAN segment includes a customer edge bridge, and where the provider network has one or more provider edge bridges coupled to the customer edge bridges, comprising:

• in each edge bridge of a LAN segment having a multi-homed connection to the provider network, a customer edge bridge comprising a processor for flagging topology change notifications (TCNs) which relate to topology changes which affecting paths of data units through the provider network;
• and
• in each of the provider edge bridges coupled to a customer LAN segment a processor for:
• receiving topology change notifications (TCNs) from the customer network;
• in response to receiving a flagged TCN, flushing an address memory file associating end host addresses with ports of the provider edge bridge;
• and
• in response to receiving an unflagged TCN, passing the TCN without generating an address memory file.