Optimal resource assignment to maximize multistate network reliability for a computer network Yi-Kuei Lin, Cheng-Ta Yeh

Optimal resource assignment to maximize multistate network reliability for a computer networkYi-Kuei Lin, Cheng-Ta YehAdvisor : Professor Frank Y. S. LinPresented by: Tuan-Chun ChenPresentation date: May 8 , 2012

,

20101AgendaIntroductionProblem formulationDevelopment of MSNRA-GAExperimental resultsConclusions and further research

agenda2AgendaIntroductionProblem formulationDevelopment of MSNRA-GAExperimental resultsConclusions and further research

introduction

3IntroductionHow to evaluate and enhance network reliability is an important issue for organizations, especially to maximize network reliability. search for the optimal resource assignment (RA)

The multistate network (MSN) reliability is the probability that the maximal flow of the MSN is no less than the demandpaper network reliability , resource assignment, reliability.topology

Multistate networkMSNnetwork edgecapacityfailMSNreliabilityMSNMaximal flow demand 4IntroductionThe existed optimization problems of MSN reliability are categorized into two types:

(1) Achieving the optimal MSN reliability subject to different constraints .

(2) Minimizing the resources needed for providing a required reliability level. MSN reliability

MSN reliability5IntroductionMany researches involve the issues of network structure, flow assignment, and commodity allocation.

This paper focuses on searching for the optimal resource assignment with maximal MSN reliability.(MSNRA problem)

Resources denote transmission lines of a computer network.

The MSNRA problem is solved at the design phase. network structure , flow assignmentcommodity allocation

MSNRA problem

Resources

MSNRA design phaseformulatecost

6IntroductionImplicit enumeration method can be applied intuitively to solve the MSNRA problem, but it is very time-consuming.

This Study develops an optimization method named MSNRA-GA (genetic algorithm) based on the simple GA (SGA) architecture.Chromosome resource assignment.Fitness value of a chromosome MSN reliability.Evaluated in terms of MPs.MSNRA problemImplicit enumeration method

(simple GA)MSNRA-GAsolutionfitness valueMSN reliabilityMinimal path MSN reliability7IntroductionHigher MSN reliabilities have higher possibility to be preserved and to propagate their offspring.

Thus, MSNRA-GA can avoid searching for the worse solutions and the optimal solution can be found in a reasonable time.MSN reliabilities MSNRA-GAiteration8AgendaIntroductionProblem formulationDevelopment of MSNRA-GAExperimental resultsConclusions and further research

problem formulation9Problem formulationMultistate network

(N,E) a network that has a single source s and a single sink t.NSet of nodesE{i|1,2,...,q}, set of q edgesmp1, mp2...,mpzAll MPs of the network{j|1,2,...,m}, set of m resources, in which each resource j has multiple capacities, 0=hj(1)