Design of Multiple Spanning Trees for Traffic Engineering in Metro Ethernet

Ethernet has grown from its roots in the home and office environment to contend in previously uncharted territory of MANs and WANs. However, deploying Ethernet in MAN requires considerable upgrades. In this paper, we focus on the traffic engineering problem based on the construction of multiple spanning trees, which is significantly impacted by the link cost metric. In order to achieve a good load balance and decrease the average delay of the network, we propose to use a configurable link cost metric which is a function of both current link load and link delay. Simulation results reveal that the proposed link cost metric provides better performance than previously advocated metrics, and is also more flexible.