Leveraging legacy software in clean-slate network architectures

To address shortcomings of the current Internet, many researchers are taking a clean-slate approach toward re-designing the Internet. These so-called clean-slate approaches discard the old assumptions, design principles, and constraints of the current Internet, set aside concerns about compatibility with existing software, and rebuild the entire network from scratch. Clean-slate approaches have the potential to produce a completely new Internet with new features and applications. However, clean-slate approaches are rarely backward compatible, thereby rendering existing legacy software and applications useless. Rewriting huge numbers of existing legacy applications to run in a clean-slate environment is simply not practical. This paper attempts to address this challenge of running legacy software on a clean-slate network architecture. We propose a general framework that supports a translation and policy interface by which users and administrators (or applications) can map legacy software onto emerging clean-slate networks. Using the framework, users are able to take advantage of the features of a clean-slate network while running existing applications. To check the correctness and completeness of our framework, we implemented an initial prototype and applied it in the context of our clean-slate Postmodern (PoMo) Internet Architecture. Using our system we show how existing applications can make use of, and benefit from, PoMo's multi-path routing capabilities.