Tandem connection monitoring in the MPLS network

A method to monitor the quality of a MPLS LSP at the user, the service provider and the network provider's aspect is suggested. The CV packet of the MPLS OAM packets is modified, and one bit for checking the incoming error is defined, the BIP-8 byte is added to evaluate the signal quality at the service provider and the network provider level respectively. By performing the tandem connection monitoring like the above the possible conflict between network providers can be avoided as the error location will be clearly identified.