Packets’ Congestion Management with Fuzzy Admission Control Policy for Differentiated Service Networks

Abstract

This study presents a priority-based admission control system for ensuring stability in a differentiated service network using a fuzzified admission policy. Packets of varying sizes of data were transmitted from N sources through a traffic conditioner which categorizes the packets into two independent sources, consequently classifying them into “high” and “low” priorities. While class A packets are not denied admission into the buffer, this is not the case with packets of class B. Arrivals from both sources follow a Poisson distribution process of\(\alpha\)(k) = (\(\lambda\) /k!)e -\(\lambda\) . It is assumed that r > h / \(\mu\) in order to avoid a situation in which a class B arrival is denied admission while the system is empty. The arrival rates \(\lambda\) 1 \(\in\) [02\(\mu\) ) and \(\lambda\)2 \(\in\) [02 \(\alpha\)) serve as fuzzy inputs with four linguistic values while the output is a decision, d. Simulation started with an initial state, zero and system performance for the first 300time units was monitored. Results indicate that the admission controller admits arriving class B packets provided that the value of y ≤ 4 while it denied admission to arriving class B packets when y > 4, thus giving a threshold policy of y=4 . Arrivals denied admission are dropped and transmitted to the “tree manager” via the bottleneck router. These packets are arranged as nodes in an AVL tree structure which adopts tree properties to manage and transmit nodes to the buffer based on node rotations.