wiki:2012/Projects/OpenFlowMF

Version 1 (modified by aravind, 5 years ago) (diff)

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Project Participant: Aravind Krishnamoorthy

Project Objective:

To implement MobilityFirst's storage aware routing protocol "GSTAR" using OpenFlow?.

Motivation:

Traditionally, routing protocols are implemented as distributed algorithms running on several network devices that communicate with each other to keep the routing information converged. This has certain drawbacks such as the time it takes to recompute routes in case of link failures and the performance limitation of software implementations (such as ones using Click). However, if we can program the switching fabric to route packets based on rules that conform to the desired routing protocol, then a much higher throughput can be achieved. This is the idea behind OpenFlow?. A central controller which can see a map of the entire network, runs the routing algorithms, and installs appropriate flow rules on the switches to make them act like routers. Hence the architecture is one where a central intelligent controller defines how packets are handled by several dumb network elements, instead of the traditional method of using several intelligent network devices working in conjunction with each other. In this way, we can not only implement routing protocols on a switch, but also program the controller such that back up flows are installed immediately if links or devices in the network go down.

Work Log:

Analysis:

Experiments:

  • First, we choose one metric as 'signal strength' based on which we want to provide multiple network interfaces to the network.
  • We performed emulation of wifi interfaces with varying signal strength using orbit testbed. We set one node as clients and 3 nodes as access points and then scanned the access points from the client. We got a list of 3 access points and then we varied the attenuation between the client and the access points to get varied signal strength.
  • Manually scan the signal strength of different access points in the WINLAB and get an estimated mapping of distance vs signal strength. Then reproduce those values of signal strength by emulating the attenuation on Orbit Testbed.

Results & Performance Evaluation:

Results:

Attachments (5)

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