Patent ID: 8644325

Claim:
A method of obtaining network resource path metrics between a plurality of Border Nodes, BNs, in a first domain in a communication network, wherein the method is performed in a Routing Controller, RC, and the path metrics are obtained from a Path Computation Element, PCE, the method being characterized by the steps of: sending by the RC to the PCE, a first message requesting the PCE to compute a first path computation between each pair of BNs in the first domain, the first message containing a maximum metric-value indicating a maximum bound that a path computation must not exceed for a Path Computation Client, PCC, to consider the path computation acceptable; receiving by the RC, a first response from the PCE, the first response including a computed first path computation for those BN pairs for which the first path computation does not exceed the maximum metric-value contained in the first message, the first path computation providing a determined path metric between each BN pair; sending by the RC to the PCE, a second message requesting the PCE to compute a subsequent path computation for each of the BN pairs for which the first path computation did not exceed the maximum metric-value, the second message containing a minimum metric-value indicating a minimum bound that a path metric must exceed for the PCC to consider the path metric acceptable, wherein the minimum metric-value is based on the determined path metric received in the first path computation; and receiving by the RC, a second response from the PCE, the second response including a computed subsequent path computation for those BN pairs for which the subsequent path computation exceeds the minimum metric-value contained in the second message.