Presented Presented by :by :Sagar Kumar Sagar Kumar GuptaGuptaReg.no.-Reg.no.-0060031100600311 Dept. of EEE Dept. of EEE cochin cochin university of university of science and science and technology,technology,cochin.cochin.

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•What is ZigBee ?•ZigBee Overview •IEEE 802.15.4 WPAN•ZigBee Networking Basics•Technology Comparisons•Applications•Conclusion•References

What is ZigBee ?• ZigBee is a wireless networking technology.• ZigBee is the set of specifications built around

the IEEE 802.15.4 wireless protocol. • ZigBee technology is a low data rate, low power

consumption, low cost, wireless networking protocol targeted towards automation and remote control applications.

• ZigBee ideal for harsh radio environments in isolated locations.

Need for ZigBee

• ZigBee was created to satisfy the market's need of a standards-based wireless network that is– cost-effective– supports low data rates– low power consumption– secure and reliable

• ZigBee is the only wireless standards-based technology: – that addresses the unique needs of remote monitoring &

control, and sensory network applications. – enables 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

ZigBee Alliance

• The ZigBee Alliance is an association of companies working together to enable reliable, cost-effective, low-power, wirelessly networked, monitoring and control products based on an open global standard ( IEEE 802.15.4 PAN )

• Open and global

► Anyone can join and participate

► Membership is global

Why the name ZigBee ?

• The name "ZigBee" is derived from the erratic zig zag patterns many bees make between flowers when collecting pollen. This is suggestive of the invisible webs of connections existing in a fully wireless environment, similar to the way packets would move through a mesh network.

IEEE 802.15.4 WPAN

• Wireless personal area networks (WPANs) are used to convey information over relatively short distances.

• The main features of this standard are network flexibility, low cost, very low power consumption, and low data rate in an adhoc self-organizing network among inexpensive fixed, portable and moving devices

ZigBee Characteristics ZigBee operates is one of three license free bands

2.4 GHz, 915 MHz for North America, and 868 MHz for Europe

At 2.4 GHZ, there are a total of 16 channels available with a maximum data transfer of 250 kbps

At 915 MHz: 10 channels for a max 40 kbps transfer rate

At 868 MHz: 1 channel for a max 20 kbps transfer rate ZigBee incorporates a CSMA-CA protocol

This protocol that reduces the probability of interfering with other users and automatic retransmission of data ensures robustness.

Yields high throughput and low latency for low duty cycle devices like sensors and control.

 

ZigBee Characteristics

Multiple topologies : star, peer-to-peer, mesh topologies

Low power consumption with battery life ranging from months to years

128-bit AES encryption – Provides secure connections between devices

Addressing space of up to 64 bit IEEE address devices Up to 65,535 nodes on a network

Optional guaranteed time slot for applications requiring low latency

Fully reliable hand-shake protocol for transfer reliability

Range: 10 to 100m. Typical (Up to 400m max.)

DEVICE TYPES■ There are three different ZigBee device types

■ The ZigBee (PAN) coordinator node

■ The Full Function Device (FFD)

■ The Reduced Function Device (RFD)

ZIGBEE TOPOLOGY ZigBee Supports 3 TopologiesStar topologyPeer to Peer topologyCluster Tree or Mesh Topology

STAR TOPOLOGY

PEER TO PEER TOPOLOGY

CLUSTER TREE CLUSTER TREE TOPOLOGYTOPOLOGY

ZigBee ZigBee ArchitectureArchitecture

802.15.4 MAC

ZigBee Application layer

ZigBee Network layer

802.15.PHY868 /915MHz

802.15.4 PHY

2.4 Ghz

IEEE

ZigBeeZigBee

ALLIANCEALLIANCE

Network Layer AND Network Layer AND Application LayerApplication Layer

This level in the ZigBee architecture includes

The ZigBee Device Object (ZDO)

User-Defined Application Profile(s)

The Application Support (APS) Sub-layer.

PHY LAYER

The PHY service enables the transmission and reception of PHY protocol data units (PPDU) across the physical radio channel.

The features of the IEEE 802.15.4 PHY physical layer are

Activation and deactivation of the radio transceiver, energy detection (ED),Link quality indication (LQI),Clear channel assessment (CCA),Channel selection.

MAC LAYER

The MAC service enables the transmission and reception of MAC protocol data units (MPDU) across the PHY data service.

The features of MAC sub layer are Beacon Management, CSMA-CA Mechanism, GTS management, Acknowledged frame delivery,

DATA TRANSFER• Information in a ZigBee network is transferred in

packets• Each packet has a maximum size of 128 bytes,

allowing for a maximum payload of 104 bytes.• The ZigBee specification supports a maximum data

transfer rate of 250 kbps for a range of up to 100 meters

• A ZigBee network has an optimal super frame structure with a method for time synchronization

• For priority messages, a guaranteed time slot mechanism has been incorporated . This allows high priority messages to be sent across the network as rapidly as possible.

DATA TRANSFER

BEACON MODE NON-BEACON MODE

DATA TRANSFERDATA TRANSFER

BEACON MODE NON-BEACON MODE

ZIGBEE MESH ZIGBEE MESH NETWORKINGNETWORKING

TECHNOLOGY TECHNOLOGY COMPARISIONSCOMPARISIONS

CONCLUSIONCONCLUSION• Comparing ZigBee technology with the present

Bluetooth technology it is evident that ZigBee can have a safe future in this effervescent world of technology.

• There is definitely a place on the market for ZigBee, since no global standard exists today in the wireless sensor network area.

REFERENCESREFERENCES• Understanding ZigBee , July 2009.

• ZigBee “ wireless sensors and control networks” presented at Wireless Congress 2008.

• ZigBee “ the green wireless solution” published by Bob Heile, Chairman, ZigBee alliance - December 1, 2008.

• ZigBee Technical Overview , Tokyo Members Meeting Open House, Tokyo, Japan - February 28, 2008.

Websites :-Websites :-• 1. http://www.technologyreview.com/articles/zigbee

• 2. http://www.zigbee.org

• 3. http://www.wisegeek.com