Network operating methods provide a first packet switch configured to send a plurality of packets from the first packet switch to a second packet switch via a network path traversing one or more intermediate packet switches, access data describing at least one performance characteristic of the network path, and based on the data, modify a rate at which the first packet switch sends the plurality of packets to the second packet switch via the path. Network management methods receive data describing at least one performance characteristic of a network path having a first endpoint on a first packet switch, a second endpoint on a second packet switch, the network path traversing one or more intermediate packet switches and, based on the received data, instruct the first packet switch to modify a rate at which the first packet switch sends packets to the second packet switch via the network path.