1. 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

2. 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

3. 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)

4. SDN Control plane and forwarding plane Controller
Centralized management
Controller
NOX, POX
Span across multiple LANs.

5. FlowVisor – slicing
Wireless SDN
Time required

6. 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

7. 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

8. Handoffs Manage multiple handoff situations
Homogeneous
Heterogeneous
Seamless handoff between service providers is trickier

9. 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

10. 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

11. Security Localization
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

12. Conclusion
Letting operators or ISPs collaborate and exchange status information
Commercial issues
Privacy issues
Topography
Cost

13. Reference http://www.noxrepo.org/
P. Dely, A. Kassler, and N. Bayer. Openflow for wireless mesh networks. In 20th International Conference on Computer Communications and Networks (ICCCN), Aug