IEEE 802'15'3: Highrate WPAN Overview

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IEEE 802.15.3High-rate WPAN Overview
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Outline

• IEEE 802.15 Family
• Requirements of IEEE 802.15.3
• Layer Model
• IEEE 802.15.3 Standards
• Network Topology
• Network Operations
• Frame Architecture
• QoS Security

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IEEE 802.15 Family

• Wireless Personal Area Networks (WPAN)
• Communication within a persons operating space
  (10m)
• Short range / Low power / Low cost / Small
  networks
• IEEE 802.15 family
• IEEE 802.15.1 (Bluetooth)
• IEEE 802.15.3 (WiMedia)
• IEEE 802.15.4 (ZigBee)
• IEEE 802.15.2 defines the coexistence of WPAN
  with other wireless devices operating in
  unlicensed frequency bands

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WiMedias Mission Statement
To promote wireless multimedia connectivity and
interoperability between devices in a personal
area network.
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Why a New Wireless Standard?

• No previous wireless standard has been optimized
  for multimedia.
• Wi-Fi, Bluetooth and others include core
  optimizations (down to the MAC PHY) for their
  target markets.
• A Multimedia solution needs to have
• simplicity of use
• advanced QoS
• low cost (low complexity)
• support long battery life
• sufficient data rate and spatial capacity
• a scalable security platform

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WiMedia Membership
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Initial WiMedia Focus AV Clusters

• Including
• DTV / HDTV
• Set Top Box (with Internet connection)
• AV Receiver Speakers
• DVD Player
• PVR Storage, Multimedia Server DVD-RW
• Game Console
• Mobile Device
• Camcorder, Digital Camera
• Personal Entertainment Devices (e.g., MP3)
• Mobile phone
• Remote Control

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AV Cluster Profiles

• Streaming Media
• Video (compressed uncompressed)
• Audio (surround sound systems)
• Connection Management Device Discovery
• Native Discovery (minimal but useful)
• Higher Level should leverage existing protocol
  (such as uPnP or 1394)
• IP Specification
• Support for IPv6
• Ethernet Encapsulation?

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WiMedia for A/V Distribution

• Protocol stack defined for wireless distribution
  of A/V content.
• Support synchronized point to multipoint
  distribution.
• A/V transport profile
• Transport of media packets
• Signaling link establishment negotiation of
  streaming parameters.
• Monitoring application parameters adapted to
  radio link quality
• A/V control profile standardize control to all
  types of interfaces
• Service Discovery Protocol

A/V Applications
A/V Transport
A/V Control
802.15.3 MAC
802.15.3 PHY
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Layer model
TCP/IP
IEEE 802.2 Logical Link Control (LLC)
Wireless FireWire
Wireless USB
802.2 FCSL (mandatory)
IEEE 1394 FCSL (optional)
USB FCSL (optional)
802.15.3 Medium Access Control (MAC)
IEEE 802.15.3
802.15.3 PHY 11, 22, 33, 44, 55 Mbit/s
802.15.3a PHY Ultra Wide Band (UWB)
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IEEE 802.15.3 Channels

• IEEE 802.15.3 (2003 June)
• Unlicensed 2.4 GHz ISM band (2.4G2.4835G,
  83.5MHz)
• 11, 22, 33, 44, 55 Mbit/s

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UWB Channels (cont.)

• FCC recently assigned 3.110.6 GHz to UWB.
• Transmission is based on impluse radio.
• PHY There are now two major technologies for
  transmission.
• DS-UWB
• a combination of single-carrier spread-sprecturm
• MBOA (OFDM)
• multi-band spread-spectrum with multiple antennas

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Power Management

• The spec. allows devices to periodically go into
  active modes, so as to dynamically adjust their
  hibernation duty cycles.
• by informing and negotiating with their neighbors
  their hibernation/active cycles.

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Network Topology

• Piconet (10m range)
• Peer-to-peer communication between devices
• Piconet Coordinator (PNC) is responsible of
  piconet management (beacons, timeslot
  reservation)
• may have child piconets
• Maximum of 243 devices in a piconet
• Piconet Identifier (PiconetID) is used for
  identifying the piconets

Piconet relationship
Neighbor piconet
Piconet
Child piconet
Data transfer
Child PNC
Neighbor PNC
Piconet Coordinator (PNC)
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Different Piconet Types (1/2)

• If there are no free channel, a device may create
  a dependent piconet
• If two piconets operate in the same channel, one
  is parent piconet and other is dependent piconet
• Dependent piconet
• Child piconet
• PNC belongs as a device in the parent piconet
• Extends the coverage area of the piconet
• Neighbor piconet
• Does not extend the coverage area
• Dependent piconets are
• Autonomous
• They have distinct PiconetIDs
• They use a dedicated time slot from the parent
  PNC called Channel Time Assignment (CTA) to share
  the time between piconets

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Different Piconet Types (2/2)
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Responsibilities of Piconet Coordinator (PNC)

• Periodically sends beacon frames containing
  necessary information for piconet operations
• Supplies timing with the beacon
• Manages QoS, power save modes, and access control
• Assigns time slots to each device and distributes
  payload protection keys
• All devices are not required to be able to act as
  PNC
• This enables cheap and simple implementations

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Network Operations - Piconet Creation

• Device must make sure that there are no existing
  piconets using the same channel
• Passive scanning is used to detect existing
  piconets
• Device listens the beacon frames from PNCs
• A device creating a piconet becomes PNC and has
  the following responsibility
• Selects the channel
• Starts to transmit beacon frames

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Network Operations - Joining to the Piconet

• Piconets are discovered using passive scanning
• Device authenticates with PNC
• Device exchanges the capability information with
  PNC (PHY data rates supported, power management
  status, buffer space, capability to act as PNC
  etc.)
• Device sends association request to join the
  piconet
• PNC sends association response
• After joining to the piconet, the device
  information is broadcast with the beacon

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Network Operations PNC Handover

• Changing PNC during the operation (PNC handover)
• When active PNC leaves the network or runs out of
  battery, another device may take over PNC
  responsibilities
• When new device joins the piconet
• If the new device is more capable and the current
  security policies allow it, then the PNC has the
  option of handing over control of the piconet to
  the device that has just joined
• PNC handover maintains all existing time
  allocations so that there is no interruption in
  the delivery of data in the piconet
• PNC selects the best device among those that have
  the PNC Capable bit set

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Frame Architecture

• CAP
• Allows contention via CSMA/CA
• Command exchange between DEV and PNC
• File transfers from DEV without request
• CTA (channel time allocation) Period
• Time slot allocation specified in the beacon
• Reserved bandwidth for DEV
• MCTA command (PNC?DEV)
• CTA data (DEV?DEV)