The aim of this paper is to propose modified pushout mechanism and present approximate traffic analyses in ATM network. Cells generated by different type of traffic sources face different priority schema entering the ATM switch: Deterministic traffic generated by real-time services like telephone and video obtain higher priority; Elastic traffic or data services are considered to be non-delay sensitive and obtain lower priority. Because of the different nature of the used services, the throughput of elastic traffic is bound to be significantly lower than real time traffic, even sees a collapse as the ATM switch is overloaded. This is resulting in disparity with respect to elastic and real-time traffic. The mechanism proposed here aims at overcoming this unfairness during dynamic share of ATM links within elastic and real-time traffic.
Cell delays and losses are correlated and have different influence on different type of services. Cell delays are a matter of importance for real-time services like telephone and interactive video services. Elastic traffic is more sensitive to the probability of cell loss. Both parameters have to be kept in given thresholds for all kind of broadband services. End-users can negotiate quality of service parameters in accordance with their specific requirements. There are 3 types of packet-level throughput: packet loss ratio (PLR), goodput and badput. PLR is probability of packet discarding. The goodput is the throughput of successfully transmitted packets and is interpreted as the bandwidth usage for successful packet transmission. The badput is the throughput of corrupted packets, which provides a measure of wasted network resources.