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ZigBee. Low-power networking protocol. Presented by: Leif Millar David Jackson Chase Casgrain. Overview. What is ZigBee ? Pros and Cons Mesh Networking Security Demo Questions. What is ZigBee ?. Named after the wiggle dance a bee does when it returns to the hive.
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ZigBee Low-power networking protocol Presented by: Leif Millar David Jackson Chase Casgrain
Overview • What is ZigBee? • Pros and Cons • Mesh Networking • Security • Demo • Questions
What is ZigBee? • Named after the wiggle dance a bee does when it returns to the hive. • Wireless communication protocol typically utilized by small embedded radios. • Developed to meet demand for ad-hoc personal networks. • Demand speculated by engineers around 1998 • ZigBee Alliance started in 2002 • Based on the 802.14.5 wireless networking protocol. • Uses: Electric Meters, Thermostats, Security Systems, Light Switches, Traffic Management, 373 Projects?
Why ZigBee? • Low Power, Cost, and Size • Straightforward configuration • Good support and documentation • Lots of products already on the market • Mesh Networking • Lends itself well to many different applications • Very low wakeup time • 30mS (Zigbee) vs. up to 3S (Bluetooth)
Or maybe not… • Competes with Wi-Fi for bandwidth.. • Only four usable bands in Wi-Fi intensive scenarios • Low speed and throughput • < 100kbps Image & Data Source<http://fosiao.com/system/files/misc/zigbee.wifi_.channel.jpg>
Comparison Diagram obtained from : <http://www.telegesis.com/downloads/general/Evoluon%20Zigbee%20Presentation.pdf>
What is a Mesh Network, and why do I care? • A mesh network consists of a series of nodes. • Each node must acquire and transmit its own data, as well as act as a relay for other nodes to propagate data. • ZigBee devices often form Mesh Networks. • Examples: Wireless light switching, Music school practice rooms. Image Source:<http://kf5czo.blogspot.com/2012/03/ham-radio-and-mesh-networks.html>
Mesh Networking • Mesh networks consist of three types of nodes: • Coordinator • Router • End Devices • What does a Coordinator do? Why? • Search for open wireless channel • Establish “PAN ID” • Wait for queries from new nodes • End devices, when not in use, shut down to conserve power. They have no routing responsibilities. Mixed Star and Mesh Topology Image Source:<http://i.cmpnet.com/rfdesignline/2009/03/FIGURE_01_TI.jpg>
Mesh Networking • Advantages of Mesh Networking: • Allows devices to communicate to multiple other devices in the network. • Multiple paths to destination – greater flexibility against interference. • Allows overall network to grow to larger physical sizes than possible with point-to-point networks. • Mesh Characteristics: • Self-forming – ZigBee devices can establish communication pathways when new devices appear. • Self-healing – If a node is removed from the network (either intentionally or not) the remaining network will look to establish alternate routes of communication.
Is it safe? • High-level Wireless security: • IEEE 802.15.4 standard AES 128-bit encryption elements. • ZigBee-specific Mesh security – Uses a system of security keys (Link, Master, Network) to maintain security against: • Unauthorized network access • Packet integrity damage • Packet snooping (internal and external) Image Source:<http://www.jennic.com/elearning/zigbee/files/graphics/key_lock.jpg>
Xbee Introduction • XBee – 16 models, 3 wireless protocols. ZigBee, DigiMesh, and IEEE 802.15.4 • XBee for the demo – Xbee 802.15.4 S1 • Uses protocol 802.15.4 • No mesh network - Point to point, point to multipoint • No underlying infrastructure. • Basis for Zigbee UART – Serial Communication RX TX TX RX RX TX Transparent Serial Communication TX RX
Xbee Demo • Are you using XBee’s for your project? Pay attention • X-CTU software • Set Baud Rate • Set Destination Address – high and low
Demo Code For The Arduino Boards Master Slave
Demo Notes • Xbee– non standard pin size. • Uartinterface. Uses tx-rx. • To Program Xbee use a FTDI - Uart to usb. • Xbees uses 3.3 volts
But wait, there’s more! EECS 498 Lab http://www.eecs.umich.edu/courses/eecs498-brehob/Labs/498Lab1.pdf ZigBee Alliance www.zigbee.org http://www.zigbee.org/Standards/ZigBeeHomeAutomation/FAQ.aspx http://docs.zigbee.org/zigbee-docs/dcn/06-4482.pdf Wikipedia http://en.wikipedia.org/wiki/Zigbee http://en.wikipedia.org/wiki/Mesh_networking http://en.wikipedia.org/wiki/AODV Libelium http://www.libelium.com/security_802.15.4_zigbee/ Digi http://www.digi.com/learningcenter/video/player?id=zigbee-part-i-mesh-networking-basics Digikey http://www.digikey.com/us/en/techzone/wireless/resources/articles/comparing-low-power-wireless.html