Master of Engineering (Hons.)
Srikantashastry, Nagaraja, Performance of the ABR policer in an ATM network, Master of Engineering (Hons.) thesis, , University of Wollongong, 2000. http://ro.uow.edu.au/theses/2556
Both the Available Bit Rate (ABR) and Unspecified Bit Rate (UBR) services in Asynchronous Transfer Mode (ATM) networks cater for data traffic. The network guarantees low cell loss as a parameter for Quality of Service (QoS) in the ABR service, but not in UBR service. In order to achieve a low cell-loss ratio (CLR) for the ABR service, it is critical for the network to adopt suitable traffic management functions before and after the admission of a call. Before any call admission, the network reserves resources through the Call Admission Control (CAC) function, based on the agreed traffic contract. After a call admission, the network monitors, through a policing function, any violation of the source rate and behaviour agreed to in the contract. The policer checks the conformance (as per the conformance definition ) of incoming cells, passes those which do conform and tags/discards those which do not conform. The performance accuracy of a policer plays a key role in a network's ability to meet the guaranteed QoS. Any errors in the policing algorithm leads to poor performance, with a potential QoS short fall. This thesis proposes a performance measurement method for the ABR policer.