zigbee technology - irjcs · pdf file · 2017-05-05zigbee employment modes of...

International Research Journal of Computer Science (IRJCS) ISSN: 2393-9842 Issue 05, Volume 4 (May 2017) SPECIAL ISSUE www.irjcs.com

______________________________________________________________________________________________________ IRJCS: Impact Factor Value – SJIF: Innospace, Morocco (2016): 4.281

Indexcopernicus: (ICV 2015): 79.58 © 2014- 17, IRJCS- All Rights Reserved Page -138

ZIGBEE TECHNOLOGY

Rajanna M1, Rabiya fathima 2, Priyanka Yadav R3

1Associate Professor, 2,3UG scholar Dept. of Information Science Engineering, Vemana institute of technology, Bangalore

Abstract-- ZigBee is an IEEE 802.15.4 based specification for a group of high level communication protocols used to create personal area networks with small, low-power digital radios. It is an new wireless technology. It is a low-cost, low-power, energy efficient, wireless mesh network standard targeted at the wide development of long battery life devices in wireless control and monitoring applications. Its devices have low latency which further reduces average current. Its low power consumption limits transmission distances to 10-100 meters line-of-sight, and it can transmit data over long distance by passing data through a mesh network of intermediate devices to reach more distant ones. The technology defined by the ZigBee specification is intended to be simpler and less expensive than other WPAN such as Bluetooth or Wi-Fi. Applications include wireless light switches, electrical meters with in-home-displays, traffic management systems and other consumer and industrial equipments that requires short range low rate wireless data transfer.

1. INTRODUCTION

ZigBee is a low-cost, low-power, energy efficient, wireless mesh network standard targeted at the wide development of the long battery life devices in wireless control and monitoring applications. ZigBee is typically used in data rate application that requires long battery life and secure networking. ZigBee networks are secured by 128 bits symmetric encryption keys. It has a defined rate of 250Kbit/s, best suited for intermittent data transmissions from a sensor or input devices. Its network layer natively supports both star and tree networks and generic mesh networking. It builds on the PHY layer and media access control defined in IEEE standard 802.15.4 for low rate WPAN’s. ZigBee was conceived in 1998, standardized in 2003 and revised in 2006. The name refers to the Waggle Dance of Honeybees after their return to the beehive.

II. ZIGBEE GENERAL CHARACTERISTICS

DATA RATES OF 20KBPS AND UP TO 250KBPS CSMA/CA CHANNEL ACCESS 3 FREQUENCIES BANDS WITH 27 CHANNELS SUPPORT FOR LOW LATENCY DEVICES VERY LONG BATTERY LIFE EXTREMELY LOW DUTY CYCLE (<0.1%) LOW POWER USAGE CONSUMPTION SUPPORT LARGE NUMBER OF NODES

III. ZIGBEE EMPLOYMENT MODES OF COMMUNICATION

The current ZigBee protocol support Beacon and Non-Beacon enabled networks. In Beacon enabled networks, the special network nodes called ZigBee routers transmit periodic beacons to conform their presence to other network nodes. Nodes may sleep between beacons, thus lowering their duty cycle and extending their battery life. In beaconing networks, nodes need to be active while beacon is being transmitted. They may range from 15.36milliseconds to 251.65824seconds at 250Kbits/second from 24milliseconds to 393.216seconds at 40Kbits/second and from 48milliseconds to786.432seconds at 20Kbits/second. In Non-Beacon enabled networks, an unspotted CSMA/CA channel access mechanism is used. This allows heterogeneous networks in which some devices receive continously while others only transmit when an external stimulus is detected . In non-beacon enabled networks, nodes need to be active while a beacon is being transmitted.Ex:Wireless Light Switch.

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Fig. 1 : Communication Mechanisms I and II

IV. ARCHITECTURE

The architecture includes for key components, Network layer, Application layer, ZDO and manufacturer-defined application object.

NETWORK LAYER The main functions of the network layer are to enable the correct use of MAC layer and provide a suitable interface for use by the next upper layer, namely the application layer. On the one hand, the data entity creates and manages network layer data units from the payload of application layer and performs routing according to the current topology. On the other hand, there is a layer control, which is used to handle configuration of new devices and establish new networks. The routing protocol used by the network layer is AODV. To find the destination device, it broadcasts out a route request to all of its neighbors. The neighbors then broadcast the request to their neighbors until the destination is reached. Once the destination is reached, it sends its route reply via unicast transmission following the lowest cost path to the source.

APPLICATION LAYER The application layer is a highest-level layer defined by the specification and is the effective interface of the ZigBee system to its end users. It comprises the majority of components added by the ZigBee specification: both ZDO and its management procedures.

MAIN COMPONENTS ZDO: A Protocol in ZigBee protocol stack is responsible for overall device management, security keys and policies. It is responsible for defining the role of a device as either coordinator or end device. APS: It offers a well defined interface and control services. It works as a bridge between the network layer and the other elements of the application layer.

WORKING OF WIRELESS LIGHT SWITCH ZigBee node at the lamp may constantly receive; since it is connected to the main supply while a battery powered light switch would remain asleep until the switch is thrown. The switch then wakes up and sends a command to the lamp and receives an acknowledgment and returns to sleep. In such a network the lamp node will be at least a ZigBee router, ZigBee coordinator, ZigBee end device.





Fig B: ZigBee Protocol Stack Architecture

ZigBee Router: While running an application, a ZR can act as an intermediate router, passing on data from other devices. ZigBee End Device: Contains just enough functionality to talk to the parent node (either Coordinator or Router). It cannot relay data from other devices. Provides long battery life by in relationship with the nodes. ZED requires least amount of memory and hence can be less expensive to manufacture than a ZR or ZC. ZigBee Coordinator: The most capable device, the coordinator forms the root of the network tree and might bridge to other networks. There is precisely one ZigBee coordinator in each network since it is the device that started the network originally. It stores information about the network, including acting as the trust center and repository for security keys.

V. DEVICE TYPES ZigBee devices are of 3 kinds

ZIGBEE COORDINATOR(ZC) ZIGBEE ROUTER(ZR) ZIGBEE END DEVICE(ZED)

ZigBee provides facilities for carrying out secure communications, protecting establishment and transport of cryptographic keys, ciphering frames and controlling devices. It builds on the basic security framework defined in IEEE 802.15.4. ZigBee uses 128-bit keys to implement its security mechanisms.

Fig C: Types of ZigBee

Table 1:Wireless technology comparison chart





Fig D:Graph For Wireless Technology

VI. APPLICATION AREAS

Fig E: ZigBee Application Areas

Home Entertainment and Control: Home automation such as in QIVICON, smart lighting, advanced temperature control, safety and security, movies and music

Wireless Sensor Networks: Starting with individual sensors like Telosb/Tmote and Iris from Memsic Industrial Control

Embedded sensing Medical data collection Smoke and intruder warning

Building Automation VII. APPLICATION PROFILES

RELEASED SPECIFICATIONS ZigBee Home Automation 1.2 Smart Energies 1.1b Telecommunication Services 1.0 Healthcare 1.0 RF4CE-Remote Control 1.0 RF4CE-Input Device 1.0 Remote Control 2.0 Light Link 1.0 IP 1.0 Building Automation 1.0 Gateway 1.0 Retail Services





SPECIFICATIONS-UNDER DEVELOPMENT ZigBee Smart Energy 2.0 Smart Energy 1.2/1.3 Light Link 1.1 Home Automation 1.3

ADVANTAGES

Power saving and low power consumption Reliability Low cost ZigBee protocol is patent fee free Short time delay Large network capacity Provides security

DISADVANTAGES Short range capacity Low data speed

CONCLUSION

The IEEE 802.15.4 based ZigBee is designed for remote controls and sensors which are many in numbers, but need only small data packets and extremely low power consumption for lifetime.

It is low-cost, low-power, energy efficient wireless mesh network standard targeted at the wide development of long battery devices in wireless control and monitoring applications.

The technology defined by the ZigBee specification is intended to be simpler and less expensive than other WPAN such as Bluetooth or Wi-Fi.

It has less duty cycle or less data rate compared to other wireless technologies. In terms of protocol stack size, ZigBee’s 32KB is about one third of the stack size necessary in other wireless technologies

i.e for limited capability end devices. It is most likely that ZigBee will increasingly play an important role in the future of computer and communication

technology. ZigBee technology is designed for the application areas which suits its main characteristics and features.

REFERENCES

[1]. Behrouz A Forouzan, Sophia Chung Fegan,” DATACOMMUNICATIONS AND NETWORKING “, Fourth edition, Tata

McGraw-Hill, 2006. [2]. Agarwal D. and Zeng, “INTRODUCTION TO WIRELESS AND MOBILE SYSTEMS”, Pacific Grove, CA, NJ:

Brooks/Cole Thomson Learning, 2003. [3]. Bishop.M,”COMPUTER SECURITY”. Reading, MA:Addison-Wesley, 2003. [4]. Comer, D,”COMPUTER NETWORKS”. Upper Saddle River, NJ: Prentice Hall, 2004. [5]. Peterson. L, and Davie B.”COMPUTER NETWORKS:A SYSTEM APPROACH”, San Francisco, CA: Morgan,

Kaufmans, 2000. [6]. Stallings. W, “WIRELESS COMMUNICATIONS AND NETWORKS”. Upper Saddle River, NJ: Prentice Hall, 2002. [7]. Stallings. W,”DATA AND COMPUTER COMMUNICATIONS”, Upper Saddle River, NJ: Prentice Hall, 2004. [8]. Stallings. W,”HIGH SPEED NETWORKS”, Upper Saddle River, NJ: Prentice Hall,1998.


zigbee technology - irjcs · pdf file · 2017-05-05zigbee employment modes of...

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