Electrical Engineering and Computer Science Compiling Minimum Incremental Update for Modular SDN Languages

Measurement results show that updating rules on switches poses major latency overhead during the course of the policy update. However, current SDN policy compilers do not handle policy updates well and generate large amount of redundant rule updates, most of which modify only the priority field. Our analysis shows that the lack of knowledge on the rule dependency and the consecutively distributed priority numbers are the fundamental problems behind the redundancy. In this paper, we tackle the problems through 1) a series of efficient algorithms that build rule dependency along with the compilation, and 2) an online optimization algorithm that maintains a scattered priority distribution with constant amortized cost. Our prototype evaluation demonstrates that our proposed patch eliminates nearly all the priority updates. Compiling Minimum Incremental Update for Modular SDN Languages Xitao Wen Northwestern University Chunxiao Diao Northwestern University Xun Zhao Tsinghua University Yan Chen Northwestern University Li Erran Li Bell Labs, Alcatel-Lucent Bo Yang, Kai Bu Zhejiang University ABSTRACT Measurement results show that updating rules on switches poses major latency overhead during the course of the policy update. However, current SDN policy compilers do not handle policy updates well and generate large amount of redundant rule updates, most of which modify only the priority field. Our analysis shows that the lack of knowledge on the rule dependency and the consecutively distributed priority numbers are the fundamental problems behind the redundancy. In this paper, we tackle the problems through 1) a series of efficient algorithms that build rule dependency along with the compilation, and 2) an online optimization algorithm that maintains a scattered priority distribution with constant amortized cost. Our prototype evaluation demonstrates that our proposed patch eliminates nearly all the priority updates.Measurement results show that updating rules on switches poses major latency overhead during the course of the policy update. However, current SDN policy compilers do not handle policy updates well and generate large amount of redundant rule updates, most of which modify only the priority field. Our analysis shows that the lack of knowledge on the rule dependency and the consecutively distributed priority numbers are the fundamental problems behind the redundancy. In this paper, we tackle the problems through 1) a series of efficient algorithms that build rule dependency along with the compilation, and 2) an online optimization algorithm that maintains a scattered priority distribution with constant amortized cost. Our prototype evaluation demonstrates that our proposed patch eliminates nearly all the priority updates.