Optimal forwarding in a network implementing a plurality of logical networking schemes

A non-transitory computer-readable recording medium having computer-executable instructions stored thereon for determining an optimal forwarding path across a network, the network including a plurality of gateways configured to implement respective networking protocols for switching packets over a first logical network and a second logical network, that, when executed by a gateway, cause the gateway to:

• determine a path cost over the first logical network between each of the gateways and a source node, wherein the first logical network is a Transparent Interconnect of Lots of Links (“TRILL”) fine-grained labeling (“FGL”) network;
• determine a path cost over the second logical network between each of the gateways and a destination node;
• determine an encapsulation cost difference between switching packets over the second logical network and switching packets over the TRILL FGL network;
• determine an encapsulation overhead metric associated with switching packets over the second logical network, wherein the encapsulation overhead metric is proportional to the encapsulation cost difference;
• weight the path cost over the second logical network between each of the gateways and the destination node by the encapsulation overhead metric;
• and
• select one of the gateways as an optimal gateway, wherein the selection is based on the path cost over the TRILL FGL network between each of the gateways and the source node and the weighted path cost over the second logical network between each of the gateways and the destination node.

A method for determining an optimal forwarding path across a network, the network including a plurality of gateways configured to implement respective networking protocols for switching packets over a first logical network and a second logical network, the method comprising:

• determining a path cost over the first logical network between each of the gateways and a source node;
• determining a path cost over the second logical network between each of the gateways and a destination node;
• determining an encapsulation cost difference between switching packets over the second logical network and switching packets over the first logical network;
• determining an encapsulation overhead metric associated with switching packets over the second logical network, wherein the encapsulation overhead metric is proportional to the encapsulation cost difference;
• weighting the path cost over the second logical network between each of the gateways and the destination node by the encapsulation overhead metric;
• and
• selecting one of the gateways as an optimal gateway, wherein the selection is based on the path cost over the first logical network between each of the gateways and the source node and the weighted path cost over the second logical between each of the gateways and the destination node.