Abstract: In a packet-switched network, a distributed performance measurement system is disclosed. In each node, a node monitor maintains information for each virtual channel passing through the node, including a list of the arrival times of the packets queued for the virtual channel. In addition, each node determines node performance characteristics, which may include throughput, effective rate, delay, loss rate, and occupancy. The network further includes a network monitor, which periodically collects the node performance characteristics from each node and determines performance characteristics for each virtual channel in the network, end-to-end. The network performance characteristics may include throughput, effective rate, delay, loss rate, and occupancy. The results are useful for network operators and users to optimize the network and/or their use of the network.