Download - Dipankar Raychaudhuri, Joseph B. Evans, Srinivasan Seshan 2011.4.11 Sin-choo Kim [email protected]
CogNet – Architectural foundation for ex-perimental cognitive radio networks
Dipankar Raychaudhuri, Joseph B. Evans, Srinivasan Seshan2011.4.11
Sin-choo [email protected]
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Introduction Architectural foundation◦Global control plane◦PHY adaptation and network coding◦Spectrum coordination protocols◦Radio autoconfiguration protocols◦Flexible MAC layer◦Network layer protocols
Conclusion
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Contents
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Cognitive (in Webster) ◦Applying the experience gathered in one place by
one being to actions by another being elsewhere
Cognitive network◦a network with a cognitive process that can
perceive current network conditions, plan, de-cide, act on those conditions, learn from the consequences of its actions, all while follow-ing end-to-end goals
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Introduction
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Cognitive network
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Introduction
Network layer
MAC layer
PHY layer
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Global control plane PHY adaptation and network coding Spectrum coordination protocols Radio autoconfiguration protocols Flexible MAC layer Network layer protocols
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Architectural foundation
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Global control plane◦Cross layer network management overlay◦Monitor, configure and adapt the data plane module
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Global control plane(1/2)
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Provided functions◦ Initial radio bootstrapping
Rebroadcast control packets, providing global aware-ness to all cognitive radios
◦Service discovery function Edge of the service band Dedicated portion of a TDMA frame
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Global control plane(2/2)
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Network coding◦Collaborate with each other to recombine several input
packets into one or several output packets
Main benefits◦Throughput improvements◦ Increased robustness
Require GCP support ◦Path establishment
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PHY adaptation and network coding
2 + 2 = 4
2 + 1 = 3
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Agile wideband radio◦ Transmitters scan and choose their frequency band
Reactive control◦ Seek equilibrium resource allocation without explicit coordination◦ Control rate and power
Common spectrum coordination channel(CSCC)◦ Each node uses beacons containing spectrum usage information
Spectrum server◦ Coordinated spectrum usages by centralized spectrum server
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Spectrum coordination protocols
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In bootstrapping process, node aware ◦Network status◦Surrounding nodes
To conduct those process◦Obtaining PHY parameters, reachability◦Negotiate with existing sub-networks for name/service
discovery or performance optimization
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Radio autoconfiguration protocols
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Dynamically changes MAC protocols◦ ex) RTS/CTS
Where collision rarely happened, RTS/CTS is overhead
Compatible MAC Protocol◦Ensures that a pair of node can communicate directly
with each other. Nodes that are part of the same constellation must use com-
patible MAC protocols Independent constellations may make independent optimiza-
tion decisions
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Flexible MAC layer
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Overlay-based mechanisms Supernode◦Serve as a gateway between local network layers as
well as to the future Internet and its IP-based and over-lay-based networks.
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Network layer protocols(1/4)
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Naming and service discovery
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Network layer protocols(2/4)
ID
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Cross-layer aware routing◦Node can obtain information about the application traf-
fic, specified policies, link capabilities and so on◦This information will be exposed via GCP
Forwarding incentives in cognitive network◦Encourage forwarding others’ packets in ad hoc network
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Network layer protocols(3/4)
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CogNet provides the way to integrate cognitive networks into global Internet
To apply the information collected, CogNet changes three layers PHY, MAC, network layer and make be possible to communicate by using cross-layer
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Conclusion
Thank you