Design And Implementation Of Hybrid SDN Fault Localization

Probing techniques are widely used to identify faulty switches for network troubleshooting.Existing probe-based approaches for SDN fault localizationcan focus on two ways: per-rule and per-path.Both promote some certain switches to reporters by installing on them catching-rules.To avoid hindering other test packets,such catchingrules must vary between tests or be deleted before a next test,thus incurring excessive consumption on either TCAM resources of switches or bandwidth reserved for control messages.In this thesis we present a new approach,supporting hybrid fault localization in SDN.Our approach fully combines the advantages of per-rule and per-path tests,and can significantly reduces the number of catching-rules while allowing them to reside and function in switches persistently.With only one well-designed catching-rule for each switch installed,our approach can pinpoint faulty switches easily and tightly by sending test packets straight.Tests in our approach are parallelizable and catchingrules are non-invasive.The performance evaluation on realistic datasets shows that our approach is 24.0% to 92.3% faster than existing approaches.