Shared Risk Link Group (SRLG) is a failure the network is prepared for, which contains a set of links subject to a common risk of a single failure. During planning a backbone network, the list of SRLGs must be defined very carefully, because leaving out one likely failure event will significantly degrade the observed reliability of the network. Regional failures are manifested at multiple locations of the network, which are physically close to each other. In this paper, we show that operators should prepare a network for only a small number of possible regional failure events. In particular, we give a fast systematic approach to generate the list of SRLGs that cover
every possible circular disk failure of a given radius. Finally, through extensive simulations, we show that this list is surprisingly short in practice.
Tapolcai János egyetemi tanár, BME-Távközlési és Médiainformatika Tanszék, tapolcai@tmit.bme.hu
2017.július 15.