Issues with L2 abstractions and how they affect QOSbased handovers Nada Golmie Advanced Networking T

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Issues with L2 abstractions and how they affect
QOS-based handovers Nada GolmieAdvanced
Networking Technologies DivisionNational
Institute of Standards and TechnologiesGaithersbu
rg, MD 20899USAhttp//www.antd.nist.gov/seamles
sandsecure.shtml
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Media Independent Handover Architecture
User Preferences QOS
Implementation specific
Handover Decision Engine (QDE)
Application
Measurements or L2 trigger
Measurements or L2 trigger
Query or configure
Layer 3
Layer 3
Query or configure
IEEE 802.21
IEEE 802.21
Layer 3 transport
Set trigger
Set trigger
Set trigger
Trigger
Trigger
Trigger
L2
L22
L21
Access Point
Mobile Node

• What are the performance implications for the MIH
  transport protocol over layer 3?
• What are the protocol interactions and
  performance implications between the MIH layer
  being specified and layer 3 mobility protocols
  such MIPv6, HMIP and FMIP?

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QOS-based handovers building blocks

• Application QOS requirements
• Measurements characterizing the network
  performance conditions
• Consider instantaneous network conditions
  end-to-end
• Derive abstraction of link specific parameters
• A QOS-based Decision Engine (QDE)
• Considers application QOS requirements and
  network performance measurements
• Performs appropriate actions when triggers are
  received
• Signalling and information exchange
• Exchange information between various network
  entities and the QDE, including technology and
  protocol types, network measurements
• Set and relay link triggers
• For example the Media Independent Handover (MIH)
  function (IEEE 802.21) at layer 2.5

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Media Independent Handover Architecture

• Why L2 abstractions?
• Link specific parameters are not the same across
  different media types and implementations and
  therefore they cannot be used at higher layers
  without a complete description of the media and
  the implementation.
• Main issues with L2 abstractions
• Mapping function between link specific
  measurements and L2 abstractions
• Provides information to higher layers about the
  status of the link
• Configures and sets link specific thresholds
• No one-to-one mapping between link specific
  measurements and L2 abstractions
• The need to characterize the network conditions
  end-to-end
• Cached measurements from past observations and
  previous connections
• Default estimates
• Measurements can be obtained via the MIH using
  the Information service or other network nodes.

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Issues with the Media Independent Handover
Architecture
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MIH Transport Protocol Design in Mipshop

• Define the delivery of information for MIH event,
  command and information services through a layer
  3 or above protocol
• Availability of information anywhere in the
  network
• Use of MIH services even in the absence of MIH L2
  support
• Re-use of existing L3 discovery and signaling
  mechanisms
• Has received several proposals including DHCP,
  GIST, UDP and has formed protocol design team.