M.Mallikarjuna Rao -200601212 V.Harish Vyas- 200601191 Presentation - PowerPoint PPT Presentation

M.Mallikarjuna Rao -200601212 V.Harish Vyas- 200601191

Presentation Outline  Introduction  What ZigBee is?  What ZigBee does?  The Zigbee layered Model  The physical layer  The MAC layer  Packet Structure  PHY frame  Data Frame  Applications  Health Care  Home Automation

Wireless Communications  Wi-Fi  Bluetooth  X-bee  UWB  Zig-Bee

What is Zigbee Technology?  Wireless protocol for Personal Area Networking.  Designed for applications that require Low Cost Low to moderate data rates Low Power Consumption Moderate Range Security and reliability

What is Zigbee Technology?  Designed for applications that require Flexible and dynamic network topologies like Star , cluster tree and mesh network

Zigbee Frequencies  Operates in Unlicensed Bands  ISM 2.4 GHz Global Band at 250kbps  868 MHz European Band at 20kbps  915 MHz North American Band at 40kbps

Zigbee Feature Set  Ad ‐ hoc self forming networks  Star , cluster tree and mesh network  Logical Device Types  Coordinator, Router and End Device  Security  Symmetric Key with AES ‐ 128  Authentication and Encryption at MAC, NWK and Application levels  Master Keys, Network Keys and Link Keys

Star Network

Mesh Network

Cluster Network

Network devices  Coordinator  It is the starting point of the network.  It allows other devices to connect to it.  It provides binding and address-table services.  It saves messages until they can be delivered.  It is a “Full functional device” – FFD.  It is powered.

Network devices  Router  It routes messages.  It does not a start a network.  It scans network to join.  They are given a block of address to assign.  It is a Full function device – FFD.  Powered or battery depends on topology.

Network devices  End device  It does not a start a network.  It scans network to join.  It can be full function device or reduced function device.  Battery.  Gateway  Bridge between a ZigBee network and another network

ZigBee Address Architecture  Addressing  Every device has a unique 64 bit MAC address  Upon association, every device receives a unique 16 bit network address  Only the 16 bit network address is used to route packets within the network  Devices retain their 16 bit address if they disconnect from the network, however, if they LEAVE the network, the 16 bit address is re ‐ assig ned

ZigBee Address Architecture  Node Addressing

ZigBee Address Architecture  Endpoint Addressing  To control lamp 1,2,3 by Switch 1  ZigBee provides another level of sub-addressing  An endpoint number is used to identify individual switches and lamps.  Endpoint Number range 1-240.  Endpoint 0 is reserved for device management and is used to address the descriptors in the node

Zigbee Layered Model

PHYSICAL LAYER  It is responsible for wireless transmission and reception of MAC frames.  It performs the following functions  Energy detection, clear channel assessment, channel selection, data modulation and the transmission and reception of bits onto the physical medium.

MAC LAYER  Through this layer one can gain access to channels present in the network.  This layer makes it possible for several stations connected to the same physical medium to share it.

MAC LAYER  Security Services  Access Control  Data Encryption  Frame Integrity  Sequential Freshness

NETWORK LAYER  Features  Network Scan  Creating/Joining a PAN  Device Discovery  Service Discovery  Binding

Data Transfer Model  Device to Coordinator  In a beacon ‐ enable network, device finds the beacon to synchronize  Uses slotted CSMA/CA to transmit data

Data Transfer Model  Device to Coordinator  In a non beacon ‐ enable network, device transmits its using unslotted CSMA/CA.

Data Transfer Model  Coordinator to Device In a beacon ‐ enable network, the coordinator indicates in the beacon that the data is pending . Device periodically listens to the beacon and transmits a M AC command request using slotted CSMA/CA if necessary.

Data Transfer Model  Coordinator to Device In a non ‐ beacon ‐ enable network, a device transmits a MAC command request using unslotted CSMA/CA. If the coordinator has its pending data, the coordinat or transmits data frame using unslotted CSMA/CA. Otherwise, coordinator transmits a data frame with zero length payload.

PHY frame structure  PHY packet fields Preamble (32 bits) – synchronization  Start of packet delimiter (8 bits) – it  is formatted as “11100101” PHY header (8 bits) – PSDU length  PSDU (0 to 127 bytes) – data field 

Data Frame Format  Provides up to 104 byte data payload capacity Data sequence numbering ensures that packets  are tracked  Frame Check Sequence (FCS) validates error-free data

Acknowledgment Frame Format  It provides active feedback from receiver to sender that packet was received without error.

How Does ZigBee Compare?

Target Applications  Wireless sensor networks  Remote monitoring  Wireless alarms and security systems  Home/building automation  Health, sport and entertainment equipment

Health Care

Home Automation

References  http://en.wikipedia.org/wiki/ZigBee_specification  http://www.ZigBee.org  http://www.zigbee.org/en/resources/#SlidePresent ations  http://www.zigbee.org/resources/documents/IWAS _presentation_Mar04_Designing_with_802154_an d_zigbee.ppt

Thank You