Patent ID: 7620712

Claim:
Apparatus comprising: a first network element for forwarding a set of packets associated with a first set of forwarding policy indicators along a label switched path to a second network element, wherein the first and second network elements are multi protocol label switching (MPLS) label switch routers (LSRs), and wherein the first set of forwarding policy indicators is a first set of forwarding equivalence classes (FECs) associated with the label switched path; logic in the first network element for producing a first knowledge digest encoding the first set of forwarding policy indicators into a fixed length bit array, wherein the fixed length bit array is a bloom filter; logic in the first network element for periodically sending probe messages containing the first knowledge digest to the second network element; logic in the second network element for producing a second knowledge digest encoding a second set of forwarding policy indicators into a fixed length bit array, wherein the fixed length bit array is a bloom filter, and wherein the second set of forwarding policy indicators is a second set of forwarding equivalence classes (FECs) associated with the label switched path; logic in the second network element for comparing the first knowledge digest to the second knowledge digest to determine whether the first set of forwarding policy indicators is a subset of the second set of forwarding policy indicators and for sending a misbranch indication to a central processor responsive to determining that the first set of forwarding policy indicators is not a subset of the second set of forwarding policy indicators; and logic in the second network element for indicating availability of the label switched path as long as probe messages are received from the first network element in which the first set of forwarding policy indicators is determined to be a subset of the second set of forwarding policy indicators, and for indicating unavailability of the label switched path if probe messages are not received from the first network element after an interval of time.