Modular SDN compiler design with intermediate representation

Software Defined Networking (SDN) is evolving to such a phase that multiple programming languages and rule specifications coexist. However, current SDN compilers are closely bound to both languages and rules, thus disable the interoperability and compatibility of SDN programs. To solve this problem, we propose to modularize the SDN compiler by leveraging intermediate representation (IR), a common technique for computer compiler design. Specifically, we introduce Semantic Rule (SR) as the first IR for SDN compilers, which is a simple, language-independent, and semantic-preserving representation. We develop two optimizations on the semantic rule to coordinate cross-language programs in a single network and compress the number of compiled rules. We implement a modular compiler prototype with the proposed SR, and demonstrate that RYU programs can run at both OpenFlow and POF network. With synthetic network configurations, we demonstrate that the optimizations on SRs are effective, efficient and scalable.