28-01-2011, 03:36 PM
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Contents
1. The ZigBee Alliance and 802.15.4
2. Features of Protocol Stack
3. ZigBee and Bluetooth
4. Reliability Throughout the Stacks
5. Robustness Throughout the Stacks
6. 802.15.4/ZigBee vs. Bluetooth
7. Motorola 802.15.4/ZigBee™ Platform
8. An Application Example
The ZigBee Alliance and 802.15.4
1. The ZigBee Alliance is
A consortium of end users and solution providers, primarily responsible forthe development of the 802.15.4 standard
Developing applications and network capability utilizing the 802.15.4 packet delivery mechanism
Addresses application and interoperability needs of a substantial part of the market
2. IEEE 802.15.4
Composed of many of the individuals and companies that make up theZigBee Alliance
Developed the basic PHY and MAC standard with the requirement that 15.4be simple and manageable and that high‐level functionality (networking,security key management, applications) be considered
ZigBee (1/2)
1. ZigBee is designed to be a low power, low cost, low data rate, wirelesssolution.
2. ZigBee relies upon the robust IEEE 802.15.4 PHY/MAC to providereliable data transfer in noisy, interference‐rich environments
3. ZigBee layers on top of 15.4 with Mesh Networking, Security, andApplications control
ZigBee (2/2)
1. ZigBee Value Propositions
Addresses the unique needs of most remote monitoring and control network applications
1) Infrequent, low rate and small packet data
Enables the broad‐based deployment of wireless networks with low cost & low power solutions
1) Example: Lighting, security, HVAC,
2) Supports peer‐to‐peer, star and mesh networks
Monitor and sensor applications that need to have a battery life of years on alkaline batteries
1) Example – security systems, smoke alarms
What is the ZigBee Alliance?
1. Organization defining global standards for reliable, cost‐effective, low power wireless applications
2. A rapidly growing, worldwide, non‐profit industry consortium of
Leading semiconductor manufacturers
Technology providers
OEMs
End‐users
3. Sensors are one of the reasons for ZigBee!
What is ZigBee technology?
1. Cost‐effective, standards‐based wireless networking solution
2. Developed for and targets applications that need
low to moderate data rates and low duty cycles
Low average power consumption / long battery life
Security and reliability
Flexible and dynamic network topologies
1) Star, cluster tree and mesh networks
Interoperable application frameworks controlled by anindustry alliance toensureinteroperability/compatibility
The ZigBee Alliance Solution
1. Targeted at
Industrial and Commercial control/monitoring systems
Wireless sensor systems
Home and Building automation and controls
Medical monitoring
Consumer electronics
PC peripherals
2. Industry standard through application profiles running over IEEE 802.15.4 radios
3. Primary drivers
Simplicity
Long battery life
Networking capabilities
Reliability
Low cost
4. Alliance member companies provide interoperability and certificationtesting
Why do we need ZigBee technology?
1. ONLY standards‐based technology that
Addresses the unique needs of most remote monitoring and control andsensory network applications
Enables the broad‐based deployment of wireless networks with low cost, low power solutions
Provides the ability to run for years on inexpensive primary batteries for a typical monitoring application
Architecture Objectives
ZigBee Architecture Objectives
1. Enables cost‐effective, low power, reliable devices for monitoring andcontrol
2. ZigBee’s architecture developed to target environments and applicationsbest suited to the technology
3. Provide a platform and implementation for wirelessly networked devices
4. Ensure interoperability through the definition of application profiles
5. Define the ZigBee network and stack models
6. Provide the framework to allow a separation of concerns for the specification, design, and implementation of ZigBee devices
7. Allow future extension of ZigBee
How A ZigBee Network Forms
1. Devices are pre‐programmed for their network function
Coordinator scans to find an unused channel to start a network
Router (mesh device within a network) scans to find an active channel to join,then permits other devices to join
End Device will always try to join an existing network
2. Devices discover other devices in the network providing complementary services
Service Discovery can be initiated from any device within the network
3. Devices can be bound to other devices offering complementary services
Binding provides a command and control feature for specially identified setsof devices