ZigBee
http://www.zigbee.org/
Introduction
• A technological standard designed for control and
sensor networks.
• A wireless language that everyday devices use to
connect to one another.
• Mesh network specification for low-power wireless
local area networks (WLANs) that cover a large area.
Introduction
• ZigBee was designed to provide high data
throughput in applications where the duty cycle is
low and power consumption is an important
constraint.
• Industrial automation and physical plant operations,
it is often associated with machine-to-machine
communication and the Internet of Things (IoT).
Introduction
• Based on the IEEE 802.15.4 Standard
• Created by the ZigBee Alliance
• Simpler and less expensive than other wireless
personal area networks (WPANs), such as
Bluetooth or Wi-Fi.
• Its low power consumption limits transmission
distances to 10–100 meters line-of-sight,
Introduction
• Operates in Personal Area Networks (PAN’s) and
device-to-device networks
• Connectivity between small packet devices. Control
of lights, switches, thermostats, appliances, etc.
• ZigBee networks are secured by 128 bit encryption
keys.
• ZigBee has a defined rate of 250 kbit/s, best suited
for data transmissions from a sensor or input
device.
• Organization defining global standards for reliable,
cost‐effective, low power wireless applications
• A consortium of end users and solution providers,
primarily responsible for the development of the
802.15.4 standard
• Developing applications and network capability
utilizing the 802.15.4 packet delivery mechanism
Characteristics
•
•
•
•
•
•
Low power consumption
Low data rate
Relatively short transmission range
Scalability
Reliability
Flexible protocol design suitable for many
applications
• Low cost
Applications
monitors
sensors
automation
control
monitors
diagnostics
sensors
INDUSTRIAL
&
COMMERCIAL
CONSUMER
ELECTRONIC
S
TV VCR
DVD/CD
Remote
control
ZigBee
PERSONAL
HEALTH
CARE
consoles
portables
educational
LOW DATA-RATE
RADIO DEVICES
TOYS &
GAMES
HOME
AUTOMATION
PC &
PERIPHERAL
S
mouse
keyboard
joystick
security
HVAC (heating, ventilating,
and air conditioning)
lighting
closures
IEEE 802.15.4 Device Types
• There are two different device types :
– A full function device (FFD)
– A reduced function device (RFD)
• The FFD can operate in 3 modes by serving as
– Device
– Coordinator
– PAN coordinator
• The RFD can only serve as:
– Device
9
FFD vs RFD
• Full function device (FFD)
– Any topology
– Network coordinator capable
– Talks to any other device
• Reduced function device (RFD)
– Limited to star topology
– Cannot become a network coordinator
– Talks only to a network coordinator
– Very simple implementation
10
ZigBee Network Topologies
Mesh
Star
Cluster Tree
PAN coordinator
Full Function Device
Reduced Function Device
ZigBee Network Topologies
• Star Topology
– Advantage
• Easy to synchronize
• Low latency
– Disadvantage
• Small scale
• Not applicable to big numbers of nodes
ZigBee Network Topologies
• Mesh Topology
– Advantage
• Robust multihop communication
• Network is more flexible
• Lower latency
– Disadvantage
• Route discovery is costly
• Needs storage for routing table
ZigBee Network Topologies
• Cluster Tree
– Advantage
• Low routing cost
• Allow multihop communication
– Disadvantage
• Route reconstruction is costly
• Latency may be quite long
ZigBee and Bluetooth Comparison
• Optimized for different applications
– ZigBee
• Smaller packets over large network
• Mostly Static networks with many, infrequently used devices
• Home automation, toys, remote controls, etc.
– Bluetooth
•
•
•
•
Larger packets over small network
Ad‐hoc networks
File transfer
Screen graphics, pictures, hands free audio, Mobile phones,
headsets, PDAs, etc.
ZigBee and Bluetooth Comparison
Feature(s)
Power Profile
Complexity
Nodes/Master
Latency
Range
Extendibility
Data Rate
Security
Bluetooth
ZigBee
days
Years
complex
Simple
7
64000
10 seconds
30 ms – 1s
10m
70m ~ 300m
no
Yes
1 Mbps
250 Kbps
64bit, 128bit
128bit Advanced
Encryption System
and Application
Layer
Zigbee vs. Other Wireless technologies
Range
Meters
GSM
GPRS
EDGE
3G
2000
2003-4
10,000
2005
1,000
802.11b
802.11a/g
ZigBee
100
Bluetooth 2.0
Bluetooth
10
10
100
1,000
Bluetooth 1.5
10,000
Hiper
LAN/2
Bandwidth
WiMedia
kbps
100,000
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