Cluster computer simulation of buffer sharing schemes under bursty traffic load

In this thesis it is first analyzed the effect that different Average Burst Length, buffer size or number of ports have on the performance in terms of packet loss ratio on shared memory network switches using Complete Sharing as baseline for the memory allocation scheme. Three different shared memory allocation schemes - Sharing with a Minimum Allocation (SMA), Sharing with Maximum Queue lengths (SMXQ), and Dynamic Threshold (DT) - are then analyzed under varied traffic conditions in order to determine the best configuration for each tested scenario. Having determined the best configuration for each individual scheme under all the tested scenarios, DT scheme is then compared against SMA scheme, as well as SMXQ scheme in order to determine which of the conventional shared memory allocation schemes presents a lower packet loss ratio on each tested scenario. A new shared memory allocation scheme referred to in this thesis as ‘Shortest Queue First’ (SQF) scheme is evaluated. SQF aims at decreasing packet loss ratio while maintaining fairness of memory utilization. This proposed scheme is subjected to the same traffic conditions as the other schemes mentioned above; a comparison is then drawn against the conventional scheme with the lowest packet loss ratio for each scenario in order to determine the extent to which packet loss ratio decreases for a switch utilizing the SQF scheme