Localization of IP Links Faults Using Overlay Measurements

Accurate fault detection and localization is essential to the efficient and economical operation of ISP networks. In addition, it affects the performance of Internet applications such as VoIP, and online gaming. Fault detection algorithms typically depend on spatial correlation to produce a set of fault hypotheses, the size of which increases by the existence of lost and spurious symptoms, and the overlap among network paths. The network administrator is left with the task of accurately locating and verifying these fault scenarios, which is a tedious and time-consuming task. In this paper, we formulate the problem of finding a set of overlay paths that can debug the set of suspected faulty IP links. These overlay paths are chosen from the set of existing measurement paths, which will make overlay measurements meaningful and useful for fault debugging. We study the overlap among overlay paths using various real-life Internet topologies of the two major service carriers in the U.S. We found that with a reasonable number of concurrent failures, it is possible to identify the location of the IP links faults with 60% to 95% success rate. Finally, we identify some interesting research problems in this area.