1. IEEE 802.15.3: High-rate WPAN Overview

2. Outline IEEE 802.15 Family Requirements of IEEE 802.15.3 Layer Model
IEEE Standards
Network Topology
Network Operations
Frame Architecture
QoS & Security

3. IEEE 802.15 Family Wireless Personal Area Networks (WPAN)
Communication within a person’s operating space (~10m)
Short range / Low power / Low cost / Small networks
IEEE family
IEEE (Bluetooth)
IEEE (WiMedia)
IEEE (ZigBee)
IEEE defines the coexistence of WPAN with other wireless devices operating in unlicensed frequency bands

4. Requirements of IEEE 802.15.3 Main applications Requirements
Personal area multimedia: audio, video
Wireless data transfer between consumer multimedia devices
Requirements
High data rate
Low power consumption
Low cost
Fast configuration
QoS support
Security
Ad-hoc topology

5. 802.15.3 Medium Access Control (MAC)
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)
Medium Access Control (MAC)
IEEE
PHY
11, 22, 33, 44, 55 Mbit/s
a PHY
Ultra Wide Band (UWB)

6. IEEE 802.15.3 Standards (1/2) IEEE 802.15.3 (2003 June)
Unlicensed 2.4 GHz ISM band (2.4G~2.4835G, 83.5MHz)
11, 22, 33, 44, 55 Mbit/s

7. IEEE 802.15.3 Standards (2/2) IEEE 802.15.3a
Ultra Wide Band (UWB) technology based
3.1G~10.6G, 7500MHz (by FCC)
Project started December 2002
Planned 2004, delayed
MBOA (Multi-Band OFDA Alliance) : TI & Intel
DS-UWB (Direct Sequence UWB): Motorola/Freescale & OKI (Japan)
Disagreements in the task group

8. Network Topology Piconet (~10m range)
Peer-to-peer communication between devices
Piconet Coordinator (PNC) is responsible of piconet management (beacons, timeslot reservation)
Possibly child piconets
Maximum of 243 devices in piconet
Piconet Identifier (PiconetID) is used for identifying the piconets
Neighbor
piconet
Piconet
relationship
Piconet
Child
piconet
Data
transfer
Neighbor
PNC
Child PNC
Piconet Coordinator
(PNC)

9. 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

10. Different Piconet Types (2/2)

11. 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

12. 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 goes through all the channels supported by the physical layer
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

13. 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

14. 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

15. Frame Architecture CAP CTAP Allows contention via CSMA/CA
Command exchange between DEV and PNC
File transfers from DEV without request
CTAP
Time slot allocation specified in the beacon
Reserved bandwidth for DEV
MCTA: command (PNCDEV)
CTA: data (DEVDEV)

16. Quality of Service (QoS)
IEEE supports various traffic types with different QoS requirements
Best-effort data without reservations (contention based)
PNC allocates resources (slots) for devices
Devices make requests
Periodic slot reservation for synchronous data
Voice, video
Aperiodic reservation for asynchronous data
Allocates a certain time for sending packets
Bursty data transmission: file transfer etc.

17. Security (2 modes) Mode 0 - mandatory Mode 1 - optional
Device does not use any authentication or encryption methods to protect the transmitted data
Access Control List (ACL) is available
Mode 1 - optional
Provided security services
ACL
Mutual authentication
Key management: key establishment, key transport, verifying the authenticity of the keys
Data encryption
Message integrity protection (data, beacon, commands)
Freshness