摘要 |
Round trip travel time of cells in an asynchronous transfer mode (ATM) communication network is measured by injecting a time stamp into test cells in a first test instrument, transmitting these test cells to a remote node in the network, looping the test cells back from the remote node to an originating node, and detecting their arrival. Preferably the time stamps are injected into test cells configured as OAM-PM (operation, administration, and maintenance performance management) cells. A time-of-departure stamp is injected into the payload of the test cell on transmission, and a time-of-arrival time stamp is appended upon its receipt. The time-of-arrival and time of departure time stamps are compared to determine the actual round trip travel time of the cell within the network. This information can then be used to optimize network traffic flow, especially for available bit rate virtual connections.
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