FACILITATING AUTOMATIC PROTECTION SWITCHING FOR PROVIDER BACKBONE NETWORK

摘要

An existing protection mechanism is enhanced through the use of an automatic protection switching protocol data unit (APS PDU). In conjunction with transmitting Ethernet frames to a second bridge over a primary path, a first bridge transmits APS PDUs to the second bridge over a secondary path. The APS PDUs provide the second bridge with information about the protection switching mechanism being used and provide indications regarding the status of the primary path. In particular, protection switching may be facilitated by forming an APS PDU that is extended to include an indication of an identity for a trunk or a primary path before transmitting the APS PDU to the second bridge. Alternatively, after forming a regular APS PDU, protection switching may be facilitated by encapsulating the regular APS PDU with information identifying a trunk or a primary path before transmitting the APS PDU to the second bridge.