Abstract: Techniques for measuring performance between two networks are described. A first link redundancy entity (LRE) transmits a first instance of a packet to a second LRE via a first network and a second instances of the packet to the second LRE via a second network. The first instance of the packet and the second instance of the packet have a timestamp indicating a time when the first LRE transmitted the packets. The second LRE records a first arrival time for the first instance of the packet and a second arrival time for the second instance of the packet. The second LRE determines a first latency for the first instance of the packet and a second latency for the second instance of the packet. Based at least in part of the first latency and the second latency, the second LRE determines a performance difference between the first and second networks.

Abstract: A method and apparatus that promote expedited fast link failover decisions by and end station with redundant multilayer switching paths to a network are disclosed. In response to detecting a change in connectivity with an upstream link to a network, an upstream switch may send a notification to an intermediate switch with a downstream link to the end station. In response to the notification, the intermediate switch may disable (“bring down”) the downstream link to the end station. Bringing the downstream link down in this manner may cause the end station to switch (“failover”) to a different downstream link, for example, allowing the end station to establish connectivity to the network via a redundant path.