Journal Title : International Journal of Modern Trends in Engineering and Science

Author’s Name : Sathish Manoharan | S Saminathan  unnamed

Volume 03 Issue 06 2016

ISSN no:  2348-3121

Page no: 42-44

Abstract – OPENFLOW is a standard that provides an interface for programming the data plane switches. It is a protocol for remotely controlling the forwarding table of a switch and is one element of SDN. An Open-flow Switch contain one or more tables ¬that implement packet lookups and forwarding, and an Open-flow TCP channel to link to an external controller .The switch interconnects with the controller and the controller directs the switch using the Open-flow protocol. Controller can modify flow-table entries (add or delete). Thus Open-flow switches will send or discard the packets based upon the flow-table entries. So the controller can be programmed pro-actively for load balancing of servers in any fashion either in Round-Robin or Weighted Round Robin. The  implementation of this paper is to monitor the status of all the physical servers which is then passed on to controller through the shared memory module (System V IPC) and based on which, controller decides which server to choose. In this paper,Probe is used as the main element. It consists of parser, HTTP health collector and shared memory. Thus the current state of server is given to POX controller for every interval of time to allow the packets to be sent to the healthy servers. Then according to the number of servers available,any load balancing algorithm can be implemented for better performance.

KeywordsSoftware Defined Networking, Open-flow, Web Servers, Status, Controller, Shared-Memory, Parser, POX, Geographical view, Health, Policy, HTTP 


  1. “SDN Architecture Overview” (PDF). Openetworking.org. Retrieved 22 November 2014.
  2. OpenFlow protocol API Reference: “http://ryu.readthedocs.org/en/latest/ofproto_ref.html”
  3. POX: “https://openflow.stanford.edu/display/ONL/POX+Wiki”
  4. “OpenFlow: Proactive vs Reactive”. NetworkStatic.net. Retrieved 2014-07-01.
  5. M. Nick et al., “OpenFlow: enabling innovation in campus networks”, ACM SIGCOMM Computer Communication, vol. 38, no. 2, pp. 69-74, April 2008.
  6. R. C. Lucas, “OpenFlow e o paradigma de redes definidas por software,” Ph.D. dissertation, Dept. Com. Sci, Brasilia Univ., Brasilia, DF, 2013 in press.
  7. “The Road to SDN An Intellectual History of Programmable Networks” By Princeton University in press.
  8. “Software Defined Networks – A Comprehensive Survey” By IEEE fellowships in press.
  9. HTTP status “https://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html”
  10. Dynamic Load Balancing on Web Server Systems “www.ics.uci.edu/~cs230/reading/DLB.pdf”
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