Method and apparatus for measuring performance in packet-switched networks

A method for use with a network that transmits packets through virtual channels, comprising:

• determining a value related to the length of time one or more packets are present in a node wherein determining the value further includes determining effective rate for a virtual channel in the node and delay for the virtual channel in the node, wherein effective rate is based on throughput rate when there is data in a queue corresponding to the virtual channel.

A system for use with a network for transmitting packets trough virtual channels, wherein said network includes a plurality of nodes, said system designed to measure effective rate for a virtual channel in a node and for a virtual channel end-to-end, wherein effective rate is based on throughput rate when there is data in a queue corresponding to the via channel, and designed to measure delay for a virtual channel in a node and for a virtual channel end-to-end.

A system for use with a network for transmitting packets through virtual channels, wherein said network includes a plurality of nodes, said system comprising:

• means for measuring effective rate for a virtual channel in a node, wherein effective rate is based on throughput rate when there is data in a queue corresponding to the virtual channel;
• and
• means for measuring delay for a virtual channel in a node.

The system of clam 11, wherein delay includes average delay, peak delay, and delay fluctuation.

A node for use in a packet-switched network that utilizes virtual channels, including:

• a node monitor designed to maintain information for each of a plurality of virtual channels passing through said node, said information including the time of arrival of packets in a virtual channel queue in said node, and said node monitor designed to utilize said information to determine node performance characteristics of each virtual channel in said node, said node performance characteristics including at least one of the group including effective rate for a virtual channel in said node, wherein effective rate is based on throughput rate when there is data in a queue corresponding to the virtual channel and delay for said virtual channel in said node.