A Simulated Study on Impact of Preference Function on Network Selection

Objectives: Preference function represents the decision maker attitude towards the differences between networks for a given criterion. This paper studies the impact of various preference functions on network selection in a heterogeneous wireless environment. Methods/Statistical Analysis: A multiple wireless network environment is considered and network selection is performed by assessing each network with respect to quality of service, application requirements and user preferences. As the decision process involves multiple parameters, the problem is viewed to be Multiple Attribute Decision Making (MADM). For this model, Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE) an outranking MADM method is applied to select best network. Findings: PROMETHEE performs pair-wise comparison of the networks against each criterion and generates outranking flows. The positive and negative outranking flows indicate the degree with which a network is preferable or not, when compared to other networks on a specific criterion. Based on the net outranking flow, the networks are ranked from best to worst. The best ranked network is the optimal network. However, the ranking order is greatly influenced by the preference function. Application/Improvements: This paper investigates the effect of various preference functions on network selection, accuracy, ranking abnormality and network congestion for voice and streaming applications.