Measures of Self-similarity of BGP Updates and Implications for Securing BGP

Techniques for authenticating BGP protocol objects entail the inspection of additional information in the form of authentication credentials that can be used to validate the contents of the BGP update message. The additional task of validation of these credentials when processing BGP messages will entail significant additional processing overheads. If the BGP validation process is prepared to assume that a validation outcome has a reasonable lifetime before requiring re-validation, then a local cache of BGP validation outcomes may provide significant leverage in reducing the additional processing overhead. The question then is whether we can quantify the extent to which caching of BGP updates and the associated validation outcome can reduce the validation processing load. The approach used to address this question is to analyze a set of BGP update message logs collected from a regional transit routing location within the public IPv4 Internet. This paper describes the outcomes of this study into the self-similarity of BGP updates and relates these self-similarity metrics to the size and retention time characteristics of an effective BGP update cache. This data is then related to the message validation activity, and the extent to which caching can reduce this validation processing activity is derived.