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Wireless Software Defined Networks: Challenges and Opportunities

From the 2013 IEEE International Conference on Microwaves, Communications, Antennas and Electronic System(COMCAS

2013)Author(s): Claude Chaudet; Yoram Haddad Telecom ParisTech, Institut Telecom; Jerusalem College of Technology Paris, France; Jerusalem, Israel

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Outline• Introduction• Software Defined Network(SDN) and Openflow• Wireless SDN Challenges

– Slicing and Channels Isolation– Monitoring and Status Report– Handoffs

• Wireless SDN Opportunities– Improving end-user connectivity and QoS– Multi-network planning– Security– Localization

• Conclusion• Reference

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Introduction

• Wired networks – cables, complexity• Wireless networks – data rate, services• Software Defined Radio(SDR)• Spectral efficiency – two strategies• Close access points limits optimization

possibilities• Software Defined Network(SDN)

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SDN

• Control plane and forwarding plane– Centralized management

• Controller– NOX, POX– Span across multiple LANs.

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• FlowVisor – slicing

• Wireless SDN– Time required

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Wireless SDN Challenges

• Slicing and Channels Isolation– Wireless FlowVisor management– Defining more slices than the number of channels

defined by the technology is possible.• Time division multiplexing• Frequency division multiplexing

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• Monitoring and Status Report– Report the status– Two non-trivial aspects• Estimating the different wireless channels status• Topology discovery

– Control And Provisioning of Wireless Access Points(CAPWAP)

– The channels load is quite difficult to estimate– Identifying the local topology surrounding a node

is important

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• Handoffs– Manage multiple handoff situations• Homogeneous• Heterogeneous

– Seamless handoff between service providers is trickier

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Wireless SDN Opportunities

• Improving end-user connectivity and QoS– Exchange enough information• Load balancing security and access control problems

– Controller could be defined in each geographic area• With appropriate statistics sent by multiple controllers

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• Multi-network planning– Create zone-specific controllers• Reducing interferences and power

– Access points usually dispose of a limited number of transmission power levels

– n access point disposes of k power levels• Requires n． k messages emissions• Controller needs to compare k^n situations

– Capacity increase suddenly• ISP• SDN

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• Security– Reaction can be uploaded in the form of a simple

rule by the controller in all managed nodes• Localization– Controller collecting information form several

access points

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Conclusion

• Letting operators or ISPs collaborate and exchange status information– Commercial issues

• Privacy issues• Topography• Cost

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Reference

• http://www.noxrepo.org/• http://

thesis.lib.ncu.edu.tw/ETD-db/ETD-search/getfile?URN=995302024&filename=995302024.pdf

• P. Dely, A. Kassler, and N. Bayer. Openflow for wireless mesh networks. In 20th International Conference on Computer Communications and Networks (ICCCN), Aug. 2011.