Mobile ad hoc networking with a view of 4G wireless: Imperatives and challenges

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Mobile ad hoc networking with a view of 4G
wireless Imperatives and challenges

• Myungchul Kim
• mckim_at_icu.ac.kr
• Tel [phone]

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• by J. Liu and Imrich Chlamtac, Ch 1 of Mobile Ad
  Hoc Networking, Wiley-Interscience, 2004.
• Introduction
• Mobile devices
• The worldwide number of cellular users has been
  doubling every 11/2 years.
• The number of mobile connections and the number
  of shipments of mobile and Internet terminals
  will grow by another 20-50. -gt the total number
  of mobile Internet users soon to exceed that of
  fixed-line Internet users.
• Situations in which user-required infrastructure
  is not available, cannot be installed, or cannot
  be installed in time in a given geographic area.
  -gt mobile ad hoc network.
• Ad hoc networking the 4G network architecture.

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• Review of wireless network evolution
• Wireless communication characteristics

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• Review of wireless network evolution
• Wireless communication characteristics

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• Types of wireless networks
• By network formation and architecture
  infrastructure-based network, Infrastructureless
  (ad hoc) network.
• By communication coverage area
• wireless wide area networks (Wireless WANs) e.g.,
  cellular networks
• wireless metropolitan area networks (Wireless
  MANs) e.g., local multipoint distribution
  services (LMDS), multichannel multipoint
  distribution services (MMDS) and IEEE 802.16
• wireless LANs e.g., 802.11 (Wi-Fi) and Hiperlan2
• wireless personal area networks (Wireless PANs)
  10 meter range, e.g., Bluetooth and infrared
  light.
• By access technology
• GSM, TDMA, CDMA, Sattellite, Wi-Fi, Hiperlan2,
  Bluetooth, Infrared.
• By network applications
• Enterprise, Home, Tactical, Sensor, Pervasive,
  Wearable Computing, Automated Vehicle Networks.

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• Table 1.1

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• Table 1.1 cont

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• Forces driving wireless technology evolution
• The need to integrate various types of wirless
  networks
• The need to integrate wireless platforms with
  fixed network backbone infrastructure
• The need to support high-speed multimedia
  services
• The need for convergence in network
  infrastructure
• The need to support high mobility and device
  portability
• The need to support noninfrastructure-based
  networks
• The need to add location intelligence
• The need to lower the cost of wireless services
• The need for greater standard interoperability.

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• 4G wireless architecture and capabilities
• integrating different types of wireless networks
  with wireline backbone networks seamlessly and
  the convergence of voice, multimedia, and data
  traffic over a single IP-based core network.
• Network integration
• All-IP networks, e.g., VoIP
• Lower cost and higher efficiency
• Ultrahigh speed and multimedia applications
• Ubiquitous computing
• Support of Ad Hoc networking (MANET)
• Location intelligence

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• Fig 1.1

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• Mobile Ad Hoc Networks
• Characteristics and advantages

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• Table 1.2

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• Table 1.2 cont

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• Design issues and constraints
• They are infrastructureless brings added
  difficulty in fault detection and management.
• Dynamically changing network topologies
• Physical layer limitation hidden terminal
  problem, collisions, packet loss
• Limited link bandwidth and quality
• Variation in link and node capabilities
• Energy constrained operation
• Network robustness and reliability
• Network security
• Network scalability
• Quality of Service

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• Technical challenges and research overview
• Fig 1.3

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• Technical challenges and research overview
• Media access control and optimization
• Fig 1.4 and Fig 1.5

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• Media access control and optimization
• RTS and CTS before the data transmission has
  actually taken place.-gt virtual carrier sensing
• loss/collision of RTS and CTS -gt wait for a
  random backoff duration
• Multicasting and broadcasting
• Avoid the significant delays in route recovery
  caused by link failures

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• Ad hoc routing
• Frequent changes and unpredicability in network
  topologies
• Proactive routing protocols and reactive
  on-demand routing protocols
• Fig 6.1

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• Fig 6.2 and Fig 6.3

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• TCP issues
• Packet losses lt- congestion (wired), wireless
  medium, frequent disconnection from mobility, .
• Measurements using 2Mbps 802.11 MAC have shown
  that TCP throughput decreases by 50 when the
  traffic moves from the one-hop to the two-hop
  path.
• Energy conservation
• The wireless interface consumes nearly the same
  amount of energy in the receive, transmit, and
  idle states, whereas in the sleep state, an
  interface cannot transmit or receive, and its
  power consumption is highly reduced.
• Network security

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• Simulation and performance evaluation
• OPNET, NS-2, Glomosim -gt different results
• QoS and Optimization
• May be impossible if the nodes are highly mobile
• Future research directions
• Routing protocol optimization GPS, multicasting
• QoS support
• Simulation do not exceed networks of hundred
  nodes in size
• Security
• Standardization and interoperability