A learning Switch in OpenFlow 1.3

So this is our second post about a learning Switch and as promised, it covers OpenFlow 1.3. Before we go into the details, this is what you should already know about SDN and OpenFlow:

  • General SDN Paradigm, otherwise go and read this
  • A common understanding about what OpenFlow is in contrast to SDN
  • What a simple learning switch is

What we are discussing in this post is the simple switch implementation that comes out of the LINC – OpenFlow software switch project as well as some basic principals from the latest OpenFlow Protocol (OFP) specification made by the Open Networking Foundation (ONF). One of the most important things you should know about OFP 1.3.x is the so called “table pipe-lining”. In previous versions of OFP there was a FlowTable in an OpenFlow enabled switch and that table stored the logic of how traffic flows through the network. Furthermore, a SDN-Controller jumps into the game when a packet that arrives at the switch doesn’t match any of the entries in the FlowTable. If this happens, we call it a “table-miss” and the switch sends the packet to the SDN-Controller. Now consider the following: In OpenFlow 1.3.x you not only have one FlowTable in an OpenFlow enabled switch, but there are as many FlowTables as the switch supports and the process how this multiple FlowTables are handled by OpenFlow is called the “table pipe-lining”. The inital behaviour isn’t that much different. If the packet arrives at the switch, the packet is always compared to the FlowTableEntries in the first the – table-0.

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ICCLab 2013 Summer School on Cloud Computing

The 2013 Summer School on Cloud Computing is on.

From the 1st of July to the 26th, students from the Grand Valley State University as well as Zurich University of Applied Sciences will spent two weeks at each university, first stint at ZHAW and second at GVSU, enrolled into a Cloud Computing Summer School.

GVSU has entered into international-education partnerships with the Zurich University of Applied Sciences in Switzerland in June 2012. The partnerships encompass faculty, staff and student exchanges and the 2013 Summer School on Cloud Computing is a major instance of this partnership.

Students from both universities are offered a comprehensive Cloud Computing education packaged, based on a carefully chosen set of lectures and labs. Classes on latest Cloud Computing technology, e.g. OpenStack, Software Defined Networks, Cloud Performance, Cloud Automation, CloudFoundry, are complemented with the highlight, namely a lecture and lab provided by CloudSigma’s Michael Higgins, Head of Enterprise Architecture Solutions and a visit in a Swiss data center.


All Cloud Computing lectures are given by research and domain experts of the ICCLab, see below.

  • CC-0 Cloud Computing Concepts, Thomas
  • CC-1 Introduction to IaaS and CloudSigma’s Cloud, Michael Higgins/CloudSigma
  • CC-2 Introduction to OpenStack, Irena and Piyush
  • CC-3 Introduction to PaaS, Christof
  • CC-4 Cloud Automation, Andy
  • CC-5 Cloud Networking, Philipp and Sandro
  • CC-6 Hadoop (BigData Analysis), Christof
  • CC-7 Performance & High Availability Lecture, Daniele and Konstantin