Patent ID: 7088682

Claim:
A method of determining the status of a bi-directional virtual circuit in a first end system, wherein said bi-directional virtual circuit is provisioned between said first end system and another end system, said method comprising: receiving in said first end system a plurality of loopback command packets from said another end system on said bi-directional virtual circuit; sending from said first end system a plurality of loopback response packets to said another end system, wherein said another end system determines that said bi-directional virtual circuit is operational based on the reception of said plurality of said response packets; concluding in said first end system that said bi-directional virtual circuit is operational according to the determination of said another end system, wherein said concluding comprises: examining a receive frequency at which said plurality of loopback command packets are received; and determining that said bi-directional virtual circuit is operational if said receive frequency does not change substantially; and continuing to conclude in said first end system that said bi-directional virtual circuit is operational if said receive frequency does not change substantially and does not send new loopback command packets to said another end system.