Research Of Intermittent Fault Diagnosability Of Interconect Networks

With the rapid development of large high performance signal processing architectures,a multiprocessor system may contain hundreds of thousands of processors(nodes)that communicate by exchanging messages through interconnection networks.Hence,the reliability of interconnection networks has become a hotspot people research.Diagnosability of networks is one key measurement point to evaluate its self-diagnose capability.An outstanding network system model should have a high diagnosability,so that all of the fault processors can be diagnosed to be repaired or replaced.Fault types of networks includes the permanent fault and the intermittent fault.Comparing with the permanent fault,the intermittent fault is easier to be hided and harder to be diagnosed.Despite the intermittent fault is also regarded as a kind of important fault type,its research is relatively few.Hence,based on the definition and characteristics of three common models(PMC model,BGM model,MM model),this paper study the intermittent fault diagnosis.First,this paper gives the definition of crisp three cycle(in which the cnin number is no more than one).And it illustrates that many well-known interconnection networks are crisp three cycle networks.Furthermore,combined with the sufficient and necessary condition of intermittent fault diagnosis under the PMC model,the intermittent fault diagnosability of crisp three cycle network is studied.And this paper illustrates n-dimension hypercube Qn as an example,proves the intermittent diagbosability of Qn is n-1(n?3)in two ways under the PMC model.Secondly,based on the diagnostic strategies and characteristics of BGM model,this paper proves the intermittent diagbosability of a network is ti under the BGM model if and only if its minimum in-degree greater than ti.And further prove that the intermittent diagnosability is equivalence under the condition of with or without repair.And last,Illustrating a n-dimension hypercube as an example to prove the ti of Qn is n-1(n?2)under BGM model.Finally,this paper expand the research on MM fault diagnosis model.Based on the definition and character of MM model,provide the definition of ti diagnosable and Created a sufficient and necessary conditions to determine one system is ti fault daignosable system and give detailed proof.At the end of this section,it illustrates the 3-dimention hypercube as an example to prove the intermittent diagnosability of Q3 is 2.