Relating two formal models of path-vector routing

This paper unifies two independently developed formalisms for path-vector routing protocols such as the border gateway protocol (BGP), the standard inter-domain routing protocol for the Internet. Sobrinho (2003) and Griffin, Jaggard, and Ramachandran (2003) proved conditions for guaranteed protocol convergence, but as these works operate at different levels of abstraction in modeling the protocols, the relationship between them is not obvious. Here we provide a rigorous translation between these two frameworks and use it to connect the convergence results, yielding a more complete set of analysis tools than in either framework alone. We motivate our discussion by presenting an example of applying both frameworks to analyze a set of protocols; in doing so, we show how the models, in conjunction, give important guidelines for protocol design.