Method and apparatus for determining, in real-time, a statistical bandwith used in an ATM satellite communications network

A method and apparatus are provided for determining, in real-time, a statistical bandwidth being used by at least one data stream of a communications satellite 10. An outbound module 100 within a satellite 10 includes at least one buffer 104-112 for queuing a data stream received in an uplink and transmitted in a downlink. The outbound module 100 includes a switch 102 for directing packets from multiple data streams to corresponding buffers 104-112 depending upon the quality of service associated with each data stream and corresponding buffer 104-112. A packet monitor 116 monitors the data stream traffic to each buffer 104-112 in order to measure traffic parameters such as the number of packets or bits received per second by one buffer 104-112 or multiple buffers in an outbound module 100. The traffic parameters may also include a count of the packets or bits received over a period of time by one or more buffers. A bandwidth measurement module 114 calculates the statistical bandwidth associated with each data stream based upon the traffic parameters measured by the packet monitor 116. The bandwidth measurement 114 module may further calculate the statistical bandwidth actually being used by the entire outbound module 100.