Chapter 18: Grand Challenges

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Chapter 18Grand Challenges
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Grand Challenges How Make the WSNs Billion Dollar
Industry

• GRAND CHALLENGE
• ENERGY
• ENERGY
• ENERGY
• Extremely energy-efficient solutions
• In both existing and future solutions for WSNs,
  energy efficiency is the grand challenge.

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GRAND CHALLENGE
Traditional layered approach is not suitable for
WSNs!
Cross-Layer Melting

• Traditional Approach

Our View
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XLP Cross-Layer Protocol
MC Vuran and I.F. Akyildiz, XLP A Cross Layer
Protocol for Efficient Communication in
WSNs, IEEE Tr. on Mobile Computing, Nov.
2010. Prelim version Proc. of Int. Conf on Info
Science and Systems, Princeton, March 2006.

• Initiative Concept
• Receiver Contention
• Local Congestion Control
• Angle-based Routing
• Channel Adaptive Operation
• Duty Cycle Operation

XLP Cross Layer Protocol
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XLP Comparison with 5 Different Layered Protocol
Stacks

• Energy consumption ? avg. 65 reduction
• Throughput ? avg. 32 increment
• Latency ? avg. 5 increment (tradeoff)
• Goodput ? avg. 39 increment
• Implementation ? avg. 15 reduction in code space

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GRAND CHALLENGE
HOW TO REALIZE THE MAPPING??

• User Requirements/
• Applications

• Architecture
• and Topology
• Communication
• Protocols

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FURTHER GRAND CHALLENGES

• Cost Reduction to CENTS ??
• Deployment (Architecture) Decisions
• (optimum of sensors, optimum of sinks,
• optimal locations, fast deployment,
  reusability,
• terrain considerations)

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FURTHER GRAND CHALLENGES

• How to operate and maintain these networks?
• Simple Network Management Tools?
• How to solve the ENERGY problem?
• How to deal with the SCALABILITY problem?

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FURTHER GRAND CHALLENGES

• How to deal with TERABYTE of sensed
  information??
• Network Monitoring and Management
• How to integrate WSNs into NGWI ?

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Wireless Networking The Big Picture

• Cellular Networks
• 2G
• 2.5G
• 3G
• 4G?
• WLAN
• Wireless Mesh Networks
• WiMAX
• Wireless Sensor Networks
• Cognitive Radio Networks

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The Future
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Integration of Sensor Networks and the Internet

• Sensor networks are developed in isolation so far
• Recent attempts in integrating WSNs with Internet
• 6LoWPAN IPv6 for WSNs
• IPv6 packet header is compressed to sizes that
  are suitable for
• sensor devices
• Efficient integration for communication between
  an IPv6-based
• device and a sensor device
• Significant challenges still exist in seamless
  integration !!

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Integration of Sensor Networks and the Internet

• Coexistence of WLANs and WSNs at the MAC layer
• End-to-end routing between a sensor device and an
  Internet device
• Existing transport layer solutions for WSNs are
  not compatible with the TCP and UDP protocols
• Adaptive transport protocols required for
  seamless reliable transport of event features
  throughout the WSN and next-generation wireless
  Internet

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Integration of Sensor Networks and the Internet

• Internet protocols are generally prone to energy
  and memory inefficiency
• c.f. WSN protocols tailored to provide high
  energy and memory efficiency
• Fundamental differences in design principles
  necessitate novel solutions
• Significant modifications in each network are
  required to provide seamless operation

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Wireless Sensor and Actor NetworksI. F. Akyildiz
and I. H. Kasimoglu, Wireless sensor and actor
networks Research challenges, Ad Hoc
Networks, 2(4)351367, October 2004.

• Most WSNs focus on data gathering
• Wireless sensor and actor networks (WSANs) and,
  eventually,
• cyber-physical systems (CPS)
• Recent developments in robotics
• Need to perform specialized tasks, .e.g., acting
  on environment
• based on sensed events

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Wireless Sensor Actor Network Challenges

• SensorActor Coordination
• Algorithms that can provide ordering,
  synchronization, and elimination of the
  redundancy of actions
• ActorActor Coordination
• A unified framework that can be exploited by
  different applications to always select the best
  networking paradigm available
• Analytic framework to characterize the three
  planes, i.e., the management, coordination, and
  communication planes in WSANs
• Cross-layer communication for effective sensing,
  data transmission, and acting

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Wireless Multimedia Sensor Networks (WMSNs)I. F.
Akyildiz, T. Melodia, and K. Chowdury, A
Survey on Wireless Multimedia Sensor Networks,
Computer Networks, (Elsevier), 51(4) 921-960,
March 2007

• Recent progress in CMOS technology has enabled
  the development of single chip camera modules
• Microphones have for long been used as an
  integral part of wireless sensor nodes
• Focus of research in digital signal processing,
  communication networking, and control

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WMSNs Challenges

• Aggregation and fusion of both inter-media and
  intra-media are necessary
• Tradeoffs between compression at end-nodes and
  communicating raw data have yet to be clearly
  analyzed
• At the physical layer, UWB communication for
  point-to-point links has been successfully
  accomplished.
• Multi-hop communication through the UWB
  technology is still an open research issue
• Comprehensive analytical models are needed to
  quantitatively compare different variants of UWB
  and determine

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Wireless Sensor Networks in Challenging
Environments

• Underwater Wireless Sensor Networks (UWSNs)
• Wireless Underground Sensor Networks (WUSNs)

• I. F. Akyildiz, D. Pompili, and T. Melodia,
• Underwater acoustic sensor networks research
  challenges,
• Ad Hoc Networks (Elsevier) Journal, 3(3)257-279,
  March 2005.
• F. Akyildiz and E. P. Stuntebeck,
• Wireless underground sensor networks research
  challenges,
• Ad Hoc Networks (Elsevier) Journal, 4669686,
  July 2006.