Technical Reports (CIS)

Analyzing BGP Gadgets in Maude

Anduo Wang, University of Pennsylvania
Carolyn Talcott, SRI International
Limin Jia, Carnegie Mellon University
Boon Thau Loo, University of Pennsylvania
Andre Scedrov, University of Pennsylvania

Document Type Technical Report

University of Pennsylvania Department of Computer and Information Science Technical Report No. MS-CIS-11-03.

Abstract

We propose the use of Maude for automatically analyzing small topology configurations (or “gadgets”) that serve as examples of safe systems, or counterexamples showing safety problems in Border Gateway Protocol (BGP), the protocol underlying core routing decisions on the Internet. Today, analyzing these gadgets is a manual and tedious process. Researchers check these gadgets by manually constructing “activation sequences” where the nodes make successive routing decisions that form an oscillation. Our framework is built on the Maude Rewriting Logic language that provides support for specification, prototyping and analysis of concurrent distributed systems. We have developed a library specifying a generalized path vector protocol, and methods to instantiate the library with customized policies. Protocols can be simulated by specifying a network topology and routing policies to be used. They can be analyzed using Maude’s built-in search capability to look for reachable states of interest (bad or good). Using the framework, protocols or policies can be quickly checked for problems. To validate our approach, we performed stability analysis of well-known BGP gadgets.

 

Date Posted: 10 January 2011