Developments in Transportation System Networks

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Developments in Transportation System Networks
November 2009
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Intelligent Transport Systems (ITS)

• Term generally applied to technology used to
  reduce congestion and improve safety in transport
  most often road transport
• Not a new idea has been around since 1960s
• Variable-message signs in use since 1960s
• SCATS, SCOOT, TRAC traffic light control
  developed in 1970s (and still in use today)
• Intelligent transport society of America founded
  in 1991
• Intelligent transportation systems given radio
  spectrum spot by FCC in 1999 Dedicated Short
  Range Communication (DSRC)

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Convergence onto IP/Ethernet

• During the 2000s, the elements of ITS have
  amalgamated onto a single communication system
  for
• CCTV
• VoIP
• Variable sign control
• On-ramp metering
• Toll-booth systems
• Microwave vehicle detection systems
• Even bridge movement detection

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Active traffic management

• Integrated data and coordinated access to
  signs/controls enables the following actions
  dynamically in response to conditions
• Speed control
• Route control
• Quickly clearing traffic out of lanes
• Opening outer lane
• Turning on-ramp controls on/off

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Next step - Communicate with the vehicle

• Current methods communicate with the driver
• Aimed mostly at congestion reduction
• Now the scope is broadening to take in safety
• To make serious safety gains, it is necessary to
  communicate with the vehicle
• Machines can react more quickly than people

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Vehicle communications

• Vehicle to Vehicle (V2V)
• vehicles to be informed of braking action of
  vehicles in front
• vehicles warn oncoming traffic of icy patches.
• emergency vehicles alert other vehicles of their
  approach
• awareness of vehicles in blind spot
• Vehicle to Infrastructure (V2I)
• infotainment
• Navigation
• Internet Access

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Vehicle communications
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The Car as a LAN
Low-speed data buses between electronic
components being replaced by ethernet Driven
by software upload times in repair shops
Ethernet-connected entertainment devices
installed Ethernet for external
communication
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Mobile IP evolution

• Mobile IPv4 RFC 2002 (1996)
• Defined Mobile Node, Home Agent, Foreign Agent,
  Home Address, Care-of Address
• Mobile nodes data tunnelled between Foreign
  Agent and Home Agent
• Protocol details refined in later RFCs
• Mobile IPv6 RFC 3775 (2004)
• No need for foreign agent
• No IP-in-IP encapsulation uses IPv6 extension
  headers
• Supports route optimization direct
  communication no via home network
• Uses inherent security headers
• IPv6 provides superior mobility solution to IPv4

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Mobile IP evolution cont.

• NEMO RFC 3963 (2005)
• Mobility for whole subnets, not just individual
  hosts hence NEtwork MObility
• Does not support route optimization
• Does support nesting of mobile subnets
• Suitable protocol for the V2I communication of
  In-car LANs

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NEMO problems to be solved

• Handover latency
• Acquiring new address in new foreign network
• Re-establishing connection with home agent
• Routing inefficiency and Extension header
  overheads
• Required to communicate via home network
• Extreme case aeroplane moving a network 1000s
  of miles
• Need to introduce route optimization
• IPSec overheads
• Move to certificate-based key negotiation

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Layer-1 and Layer-2 communications

• IEEE 802.11 Task Group p has developed 802.11p
  known as Wireless Access in Vehicular
  Environments (WAVE)
• Supports rapidly changing environment
• Provides fast connection establishment
• No need to agree on SSID, just use a wildcard
• Uses DSRC spectrum
• Developed with road safety applications as
  primary goal
• Acceptance that carrying commercial services
  required to speed uptake

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VANETs

• Vehicular ad-hoc Networks
• Groups of vehicles forming adhoc connections
  using 802.11p
• V2V and V2I connections

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Geographic routing - GeoNet

• Geographic routing applied specifically to VANETs
• Uses the geographic position and movement
  information of vehicles to route data packets.
• Each node maintains a location table including
  location related information for itself and a
  list of its neighbouring nodes.
• Position information, including speed and
  direction, exchanged in beacon packets
• Forwarding uses Greedy Perimeter Stateless
  Routing (GPSR) protocol

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GeoNet cont.

• Communication modes
• GeoUnicast from a node to a known location
• GeoAnyCast from a node to any node in a
  geographic area
• GeoBroadCast from a node to all nodes in
  a geographic area
• Topo-Broadcast from a node to all nodes
  a given number of hops away

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GeoNet protocol stack
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Security challenge

• Inter-vehicle communications must be secure
• Hackers could cause severe problems
• Communication relayed through intermediate
  vehicles requires privacy
• But very challenging environment for security
• Require fast inter-vehicle connection
  establishment
• Vehicles must collaborate to forward traffic
• Very little knowledge of neighbouring nodes
• Not guaranteed access to PKI certificate
  authorities

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Privacy

• If vehicles are too easily identified, they can
  be tracked, for malign purposes
• Need to use multiple certificates, and swap
  between certificates at random intervals
• Need to generate multiple IPv6 addresses, and
  swap between certificates at random intervals

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Active bodies

• C2C-CC Car to Car Communication Consortium
• non-profit organisation initiated by six
  European car manufacturers aiming to develop
  a open industrial standard for inter-vehicle
  communication
• CVIS Cooperative Vehicle Infrastructure Systems
• consortium of 60 vehicle and parts
  manufacturers, universities, research institutes,
  national road administrations. To develop
  standards and components for V2V and V2I
  communications
• SeVeCom Secure Vehiclar Communications
• EU-funded project that focuses on providing a
  full definition and implementation of security
  requirements for vehicular communications.

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Active bodies cont.

• JARI - Japan Automobile Research Institute
• IETF, ETSI, ITU, IEEE, ISO, etc
• ISO working Group CALM Continuous
  Air-Interface Long and Medium range
• Defining protocols, management interfaces,
  interoperability, for V2V and V2I communications
  over a variety of media