Flowtable-Free Routing for Data Center Networks: A Software-Defined Approach

Yi Ren, Tsung-Han Tsai, Ji-Cheng Huang, Cheng-Wei Wu, Yu-Chee Tseng

Research output: Chapter in Book/Report/Conference proceedingConference contribution

8 Citations (Scopus)
18 Downloads (Pure)


The paradigm shift toward SDN has exhibited the following trends: (1) relying on a centralized and more powerful controller to make intelligent decisions, and (2) allowing a set of relatively dumb switches to route packets. Therefore, efficiently looking up the flowtables in forwarding switches to guarantee low latency becomes a critical issue. In this paper, following the similar paradigm, we propose a new routing scheme called KeySet which is flowtable-free and enables constant-time switching at the forwarding switches. Instead of looking up long flowtables, KeySet relies on a residual system to quickly calculate routing paths. A switch only needs to do simple modular arithmetics to obtain a packet's forwarding output port. Moreover, KeySet has a nice fault- tolerant capability because in many cases the controller does not need to update flowtables at switches when a failure occurs. We validate KeySet through extensive simulations by using general as well as Facebook fat-tree topologies. The results show that the KeySet outperforms the KeyFlow scheme [1] by at least 25% in terms of the length of the forwarding label. Moreover, we show that KeySet is very efficient when applied to fat-trees.
Original languageEnglish
Title of host publicationGLOBECOM 2017 - 2017 IEEE Global Communications Conference
PublisherThe Institute of Electrical and Electronics Engineers (IEEE)
ISBN (Electronic)978-1-5090-5019-2
ISBN (Print)978-1-5090-5020-8
Publication statusPublished - 15 Jan 2018
EventGLOBECOM 2017 - 2017 IEEE Global Communications Conference - Singapore
Duration: 4 Dec 20178 Dec 2017


ConferenceGLOBECOM 2017 - 2017 IEEE Global Communications Conference

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