| 摘要 |
Management packets (36, 52, 54) are defined that are modified in the payload by each node (16, 18, 20; 24, 26, 28) along a virtual connection and are used to measure both end-to-end QoS and specific individual intermediate node performance parameters. Management packets (36, 52, 54) are implemented by defining entirely new packets or by modifying ATM OAM cells. Switches or routers for use as intermediate nodes are defined that modify the payload of the management packet (36, 52, 54) and locally measure packet delay and packet loss. An intermediate node measures and records the difference between the arrival and departure times of management packets (36, 52, 54) at that switch (31. 56) utilizing delay-stamp fields within the management packets (36, 52, 54) and either the switch internal routing header or timestamp fields (9) within the packet. At the endpoint of the virtual connection, delay-stamp fields (10) in the management packet (36, 52, 54) indicate individual node delays and the cumulative delay.
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