Patent ID: 7715403

Claim:
A method for load balanced and symmetric shortest-path-first (SPF) path selection from a source IP device to a destination IP device through a network, the method comprising: (a) advertising, from a source IP device, at least a portion of which is implemented in hardware, an output interface cost in a first direction over a first network segment between the source IP device and a destination IP device that is different from an output interface cost advertised in a second direction over the first network segment; (b) identifying, by the source IP device, a plurality of available network paths between the source IP device and the destination IP device (c) calculating, by the source IP device, a path cost for each of the available network paths from the source IP device to the destination IP device, wherein calculating a path cost includes, for paths that include the first network segment, substituting the output interface cost advertised in the first direction with the output interface cost advertised in the second direction; (d) ranking, by the source IP device, the paths based on the calculated costs; (e) selecting, by the source IP device, from the ranked paths, a lowest cost path; and (f) assigning both directions of a media session to the lowest cost path.