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CHAPTER 2

LITERATURE SURVEY

2.1 Communication between ZigBee nodes - home automation

Soyoung Hwang and Donghui Yu (2012) proposed the new design for monitoring and

controlling system in remote area using ZigBee networks and implemented. This system

designed for a home network. To monitor and control the home, web services and a smart

phone are used. They have implemented real-time remote monitoring with JMF which is a

extension API of Java. The remote controlling is carried out using ZigBee networks. The

client program in a smart phone is also implemented on the android platform. So clients can

easily monitor their house and send control commands for light using the internet or a smart

phone.

Yepeng Ni et al. (2013) describes the design and implementation of the gateway software

and hardware. The ZigBee protocol data and Wi-Fi protocol data conversion method are

introduced and they have solved the problem caused by the two different protocol

transmission rates. Then the performance of the gateway is tested and it is stable and the Wi-

Fi–ZigBee gateway is completely suitable for the needs of the smart home.

Sathya Narayanan and Gayathri (2013) introduces an intelligent home automation system

(IHAM) and they have developed the device using PIC microcontroller with the ZigBee

technology, GSM network technology and speech recognition technique that can easily control

the home appliance. This technology is utilizing low-power RF ZigBee wireless modules for

the automation centers on recognition of voice commands. All lights and electrical appliances

in a home or office are controlled by using voice commands chips with help of HM2007 chip.

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2.1.1 Reported works on Power consumption

Mario Di Francesco et al. (2011) propose cross-layer framework for energy-efficient data

and reliable collection in wireless sensor networks based on the IEEE 802.15.4/ZigBee

standards. The framework adapts an energy-aware module that captures the reliability

requirements and configures the MAC layer autonomously based on the traffic conditions and

the network topology to reduce the power consumption.

Mrunalini P Moon (2014) proposes self-pruning and forward node selection algorithms

that are assigned the hierarchical address space in ZigBee network. It needs one-hop neighbor

information and a part of two-hop neighbors are derived without transferring information

between neighboring nodes. The ZigBee will send algorithm for node selection and finds the

minimum rebroadcast nodes set.

In the research work of YashVardhanVarshney and Anil Kumar Sharma (2013), the

ZigBee transceiver‟s design methodology and simulation results at physical layer are

developed using MSK modulation technique.This paper also discusses the comparative

analysis of Zigbee transceiver system, Wi-Fi, Bluetooth and SimpiliciTI.

2.1.2 Reported works on ZigBee based Industry Automation

Qing-Ling Liu and Duk-Hwan Oh (2012) states that they have developed a Primary-Scout

Multi-Robot System (PSMRS) which is used to evaluate the efficiency of multi-hop

transmission and the data packets are delivered in an uncertain and underground laboratory

environment.

Boyina et al. (2012) have discussed the variable parameters and the CAN protocols and

these are used for the transmission and reception purpose along with ZigBee. Comparing other

wireless systems, here data transmission rate will be higher. This is user friendly application

and can be available at a minimum cost.

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Yang Li and Ke Zhang (2010) presented the characteristics as well as advantages of

ZigBee technology. They also discussed the system for hardware and software design. This

system can be applicable for remote monitoring in any environments like flammable and

explosive in nature.

AlfiyaShaikh (2012) developed a multifunction wireless communication system using

ZigBee and Wi-Fi technology. This system can achieve wireless communication, gas

monitoring, video surveillance and personnel management etc. They have discussed the best

working frequency of the WSN in coalmine. After that according to the actual environments

of coal mine, the network structure should automatically adopt cluster-tree topology. Practical

information shows that the type of communication system can satisfy safety monitor in the

coal mine tunnel.

2.1.3 Reported works on Security applications

Mukesh Kumar Thakur et al. (2013) propose a fingerprint security system based on

Zigbee wireless technology. This system is designed based on fingerprint of a user which is

obtained by a fingerprint sensor module and matching it with the user fingerprint

corresponding to the database details and shows it on the computer screen. This system will be

very much useful wherever security is the main concern.

Hashim et al. (2013) developed a new project to secure as well as monitor the car based

on combination of Zigbee, Peripheral Interface Controller (PIC) 16F877A microcontroller,

temperature sensor, vibration sensor and micro switch. The issues related to hardware and

software of Zigbee wireless monitoring system has been successfully developed.

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2.1.4 Reported works on General applications

Surendra S Dalu (2012) presented the concept of Automated ETC using ZigBee

transceiver instead of RFID technology. Here the communication range is increased and

ZigBee automated ETC can eliminate the traditional manual toll collection and it requires

minimum employee as well as lower the cost of operation. The transportation will be more

important thing in modern style of road transportation and the conventional type of manually

operated toll collection method has become outdated due to its drawbacks. Driver of vehicles

do not need to stop at toll machine and waste waiting time in a very long queue to pay their

toll. This may reduces the usage of fuel, reduce road traffic, increase road safety and passers

become pleased. ETC (Electronic Toll collection) system is generally designed for an

uninterrupted toll collection, which will become a necessary part of intelligent transportation

system

Jiasong Mu (2014) proposed a new technology called MPD (minimum physical distance)

delivery protocol based on the ZigBee in the smart grid to optimize the monitoring and

command packets transmitted from or to the ZigBee coordinator (ZC). All the packets were

forwarded with the trajectory of the nodes with the least physical depth to the neighborhoods

by introducing the concept of the physical depth. Because of the low payload of the

corresponding frames, the broadcasting technique was used to save the bandwidth and

acknowledgement was removed. They have shown the simulation results that the MPD can

easily improve the routing performance for the monitoring as well as controlling packets. They

have reduced throughput and the hop counts of the given network effectively and the end-to-

end delay was also slightly decreased.

OradeeMusikanon and WachiraChongburee (2012) have analyzed various outdoor

propagation parametersof the ZigBee and it is used as a wireless communication module in the

smart grid technology. They have collected the received signal strength (RSSI) for three

different scenarios of meter installation and analyses the path loss exponents as well as the

variance. Received signal strength indicator (RSSI) is one of the main outdoor propagation

parameters for ZigBee wireless network.

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2.1.5 Reported works on Agricultural applications

Dhumal and Chitode (2013) have proposed a greenhouse wireless monitoring and control

system based on Zigbee for solving the problems like poor real time data acquisition, more

manpower requirement and to overcome the shortcoming of the wired type system such as

complex wiring. They propose a new type of approach using the team viewer software so that

the user can easily view the required data anywhere from the world on their smart android

mobile phone as these devices are connected via Internet. Various other applications include in

Biomedical data transfer system to monitor the parameters like body temperature and gas level

etc and send the same to servers cabin, it can also be used in hazardous areas like in coal

mines, at high altitudes and in very high temperature working environment such as in steel

plants where human beings cannot monitor things properly and continuously etc.

Dhawan S Thakur and Aditi Sharma (2013) are discussing about the drip irrigation system

for agricultural fields based on ZigBee wireless technology. In this automatic microcontroller

based drip irrigation system, generally irrigation will always take place when there will be

intense requirement of water. They proposed method of an automatic irrigation technique with

minimal cost, time and human-computer interaction.

Xiaoqing Yu et al. (2012) introduced hybrid wireless sensor network architecture for

agriculture fields. This network minimizes the human involvement in agricultural information

collection systems and provides information which is more accurate than the existing wireless

sensor networks. This advanced network includes a terrestrial wireless sensor network as well

as wireless underground sensor network. This hybrid architecture combines all the advantages

of existing sensor network techniques. In particular, the WUSN provides overall collection

functionality when the specified monitoring area is not in the line-of sight of the terrestrial

wireless sensor networks, and the mobile sink nodes will provide an information acquisition

capability after collection. The network architecture of the hybrid wireless sensor networks

was described, and the deployment strategy of the hybrid sensor networks was discussed.

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Hsing-I Wang (2013) adopts research technique based on Internet of Things to construct a

green campus which will use the idea of energy-saving by regularly managing the air

conditioners and computers. When the human population grows, the resources are depleted on

earth quickly. In order to save it, governments around the world put more efforts to reduce

carbon production as well as to emphasize the benefits of less usage of energy. The

architecture of a green campus environment is established in this research. The prototype of

the given system is also demonstrated in their work.

2.2 Internet of things

2.2.1 Reported works on Home based applications

Kelly et al. (2013) have implemented effectively for monitoring regular domestic

conditions using Internet of Things technology by means of very low cost ubiquitous wireless

sensing system. They proposed this technique to provide a flexible connection mechanisms

and low-cost solution and for integrating Internet of things with general home monitoring

systems.

Mingchuan Zhang et al. (2012) have presented a new concept of Cognitive Internet of

Things (CIoT) in their research work. This technology can apperceive current wireless

network conditions, analyze the perceived knowledge from the network, make it intelligent

decisions, and perform adaptive actions in the environment, which main aim to maximize

network performance. Their cognitive process was based on proposed TNA and made up of

TCR and cooperative mechanism. The cooperative mechanism is autonomously triggered and

cognitive process autonomic runs when one node cannot fulfill the cognitive assignments.

Then game theory was used for analyzing the payoffs of multi-domain cooperation, which

illustrates these novel techniques can endows IoT with its intelligence and improve overall

system‟s performance. Finally, they have presented an example application RmCTDS to

validate the concept of their new technology CIoT.

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Thomas Zachariah et al. (2015) have proposed a general-purpose IoT gateway on smart

phones as a software service which provides ubiquitous and universal Internet access to BLE-

connected Internet of Things devices. This technique used as an alternative to the narrow,

application-specific wireless gateway hampering the development of IoT networks. Their new

technique utilizes the smart phone as both a BLE proxy (relaying profile data from the IoT

device to the cloud) and an IPv6 router for less resource-constrained endpoints (allowing IoT

devices to communicate as IP-connected hosts). This gateway problem of IoT exists in part

because gateways conflate in-network processing, network connectivity and user interface

functions. They have assumed that disentangling these functions would improve the

connectivity capacity for IoT devices. They have proposed an architecture that leverages the

ubiquitous nature of Bluetooth Low Energy radios to connect IoT devices to the Internet. We

know that Wi-Fi access points revolutionized laptop utility and the same way that a worldwide

deployment of IoT gateways could definitely revolutionize specific application-agnostic

connectivity.

SuwimonVongsingthong and SuchaSmanchat (2014) have presented about the Internet of

Things (IoT), an enabler of communication between people and things and also between

things.They have discussed about the IoT and it has to overcome huge barriers to gain trust

from people, it has also illustrated a specific potential to add a new dimension to the

application in healthcare, logistics, transportation, disaster and environment by enabling

wireless communication between smart objects. Therefore, always the IoT should be

considered as a part of the future generation Internet in which anything and everything can

connect in a network where all of the objects can interact with each other. The development of

several issues and problems will make the IoT a complete solution for the given application. If

Internet of Things has been successfully implemented, the less human efforts will benefit the

quality of life as well as business.

Emmanuel Baccelli et al. (2013) introduced RIOT OS, an OS that considersall the devices

with minimal resources available but it increases development in all range of devices. This

technique (RIOT OS) allows for standard C and C++ programming, provides real-time

capabilities as well as multi-threading, and uses only a minimum of 1.5 kB of RAM.By using

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a fixed-sized circular linked list of threads, theyhave achieved constant runtime of the

scheduler. Constant runtime of the timer‟sset of operations is achieved by exploiting the fact

that MCUs provide multiple compare registers. It is completion to maximize the time duration

spent in deep sleep modes, in order to introduce energy-efficiency also for powerful IoT

devices, so RIOT introduces a scheduler which works without any periodic events. Whenever

there will be no pending tasks, RIOT will automatically switch to the idle thread, which easily

finds the deepest sleep mode depending on peripheral devices in use. Generally interrupts

(external or kernel generated) wake up the specified system from idle state.

In this paper, Shiu Kumar (2014) has introduced and implemented an internet based

smart home system that can be easily controlled remotely upon user authentication. Using the

REST ful based web service, the Android based smart home application communicates via

internet with the micro web-server. Any android smart device can be used to install the smart

home app and monitor as well as controlthe home environment. They have developed a low

cost smart home system which requires only the microcontroller for all processing. They have

used the Google speech recognition engine instead of using an external voice recognition

module.

2.2.2 Reported works on IoT and Cloud Integration

Eli De Poorter et al. (2011) have proposed the IDRA architecture which is used to enable

connectivity between heterogeneous resource-constrained objects. The IDRA architecture can

be used for advantages. IDRA directly connects co-located objects, without any complex

translation gateways. The architecture supports backward compatibility with already existing

deployments. The architecture may be used in resource-constrained objects due to its low

memory footprint. This paper evaluates the IDRA architecture and introduces IDRA in

existing networks.

Yuichi Kawamoto et al. (2014) have introduced different classifications of IoT with

applications of using IoT technologies. They have also introduced a practical system using

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IoT, a tsunami detection system (which is composed of an active monitoring system, a satellite

and sensor terminals for real-time simultaneous utilization of the devices). Also the

requirements of the next generation systems with the IoT are delineated in this paper.

Jayavardhana Gubbi et al. (2011) have presented a Cloud centric vision of Internet of

Things for worldwide implementation. They have discussed about the enabling technologies

and new applications that are most likely to drive IoT research. They have presented Aneka

which is used for Cloud implementation in private and public Clouds.They have concluded

about the need for convergence of WSN, distributed computing and the Internet at research

community.

Stefan Nastic et al. (2014) have introduced a novel approach of software-defined

IoT units and cloud computing. Here all types of IoT resources and IoT capabilities are

encapsulated in well-structured APIs in order to provide a generalized view to access,

configure and operate IoT cloud systems.

Ning Kong et al. (2008) have discussed about the specific properties of the IOT that will

make the differences between the resource addressing in the Internet and in the IOT (RA-

IOT). The layered iteration model in the Internet is extended for their new approach of the

general layered model of the RA-IOT. They have presented the new universal resource

addressing system that can support PCS based on this model.

Conzon et al. (2015) will introduce the platform and its software architecture, describing

features like semantic devices interoperability and entity virtualization. Furthermore,

the paper will describe an innovative, IoT oriented, model driven development toolkit. This

toolkit leverages on the semantic discovery service, allowing to dynamically selecting and

locating available resources or devices, and provides a flexible instrument, including a

graphical interface, that enables developers to compose mash up applications.

HuijuanZhang and YujiShen (2014) have analyzed and proposed social features of IoT

and Sociology-based relationship model between IoT devices. This model with the automatic

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relationship recognition can enhance the autonomy and dynamics of wireless communications

in IoT. Final part of their research, the authors have presented an experiment considering real

data as a simple example and have shown the reduction of the dependency of IoT on human

intervention and make IoT devices more `smart'.

YangZhang et al. (2014) have discussed an Event-driven Service-oriented Architecture

(EDSOA) for IoT services. Distributed events act as primary techniques for all IoT service to

express its capabilities and requirements, to share meaningful independent events, and to

decouple it from other services. They discusses about to build an Event-driven SOA

infrastructure, where resource information can be used to create IoT services, use shared and

independent events to work the IoT services, and event session was used to coordinate

the IoT services. They have also given some of the applications and its experiments to show

concept proof for their event-driven SOA.

2.2.3 Reported works on Power saving applications

Bhagyalakshmi et al. (2015) are mainly concerned with the control of light or other home

appliances automatically using internet to save the human energy and electric power. This

project is designed with the help of Raspberry Pi and the microcontroller. The various devices

are connected to the sensor and microcontroller using wireless network.

Taneja (2014) has proposed a new framework which will reduce power consumption of

IoT/M2M devices as well as Gateway nodes and they used to buffer data

at IoT Application, IoT Gateways and Devices to keep devices and Gateway nodes in sleep

mode as long as possible. Generally they allow time duration to buffer this data using factors

such as predicted pattern of future IoT / M2M messages, QoS requirements and congestion

indicators from various network nodes.

Patrik Huss et al. (2014) have discussed the new approach of the Local Manager concept

with its reliable message architecture technique, modular design and variable options for local

applications as well as a flexible and compatible solution for Internet of Things. Their

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Message Relay Bridge solves problems concerning the flexibility and reliability of Wireless

Sensor Networks connected to cloud services in remote areas.

In this survey paper of Charith Perera et al. (2013), they have analyzed and discussed

context aware computing research works to understand how these challenges and difficulties

inthe field of context-aware computing have been tackled in desktop, mobile, web, wireless

sensor networks and pervasive computing fields. In their survey, they also discussed some of

the new trends in the field that were identified. Finally they have showed the importance of

context awareness in the IoT paradigm.

2.2.4 Reported works on Health related applications

Lung et al. (2013) presented new implementation of a data acquisition, which is designed

to communicate with a chest belt which canmeasure the heart rate and accelerometer data from

an EZ Chronos watch. The important goal of this work is to design and implement an

embedded system which can be applied formore number of lives assisted or medical

applications.

Mohammed et al. (2014) presented a new approach for the healthcare applications and it

consists of different technologies: communication protocols, signal processing, IOIO

microcontroller, efficient and secure mechanisms for transferring large file, the centralized

cloud and data base management system. Their research emphasizes on the specific system

and software design and architecture.

2.2.5 Reported works on Agricultural applications

Meonghun Lee et al. (2013) designed the IoT-based monitoring system which is used to

analyze crop environment and the technique to improve the decision making efficiency by

analyzing harvest statistics. Therefore they have developed the decision support system for

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forecasting agricultural production based on IoT wireless sensors. This technique was

designed as a unified system which supports selling agricultural products to consumers.

Yanbing Liu et al. (2013) have proposed a Green deployment approach for IoT called

Gemini, which emphasizes modeling and optimization on greenIoT deployment. They have

discussed some points in this paper. A hierarchical framework for general IoT deployment. An

optimization model is using proposed framework to realize the IoT toward green and less

energy consumption algorithm for finding the optimization model. Applying numerical

experiments, they have shown that the Gemini proposed in their work can work flexibly and

energy-efficiently with both random and deterministic networking settings, thus it is

applicable to the green IoT deployment.

2.2.6 Reported works on Security related papers

This paper Cherkaoui et al. (2014) addressed access control and authentication in the

structure of the IoT. It presents PUF (Physical Unclonable Functions), which can provide

secure, cheap and guaranteed secret keys to authentify specific M2M devices. This new

technology should be embedded in a generalized identity as well as access management

structure. Embedded Subscriber Identity Module (eSIM) can be used to provide

interoperability, cellular scalability with connectivity and standard compliant security

protocols. This research paper discusses an authorization approach for a resource server taking

advantage of eSIM and PUF features. IoT cases are also discussed (Building automation and

SCADA).

Sudip Misra et al. (2011) presented a new model SOA (Service Oriented Architecture)

which is mainly used as a system model for Internet of Things. SOA provides a new platform

to the application developers using which they can easily develop different applications for

IoT without any issues regarding the nature of the given objects, so it will act as a middleware.

The prevention strategy of DDoS has been mainly targeted for the architecture based on SOA

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for IoT. The researcher‟s results show that the given proposed model is very effective in

preventing any new DDoS attacks in IoT.

SyeLoongKeoh et al. (2014) discussed the new standardization efforts to enhance the

DTLS (Datagram Transport Layer Security) for IoT applications. It includes the use of

extending DTLS record Layer to protect group communication, raw public key in DTLS and

profiling DTLS for minimizing the complexity and size implementations on embedded

devices. They have provided a detail review of compression schemes that are proposed in

IETF to mitigate issues in DTLS message fragmentation.

Caiming Liu et al. (2012) proposed a new risk assessment method for IoT by Artificial

Immune System. This method includes of Detection Agent of Attack and also Sub-system of

Risk assessment dynamical. Also it adopts detector distribution technology. The simulation

result of immune principles and mechanisms in the real time IoT environment is deduced by

math set theory.

Chen Jun and Chen Chi (2014) have proposed an event-processing IDS (Intrusion

detection system) architecture in Internet of Things for IDS security requirements analysis.

The implementation of event processing for real time environments are proposed and that is

developed by Esper, a CEP engine for complex event series analysis and event processing.

Matharu et al. (2014) have described the IoT layered architecture with constituent

elements. The researchers have provided IoT architecture for a secure construction, by solving

security problems at each layer of the given architecture and also conclude by informing the

potential applications of the IoT platforms in fields varying from smart home to intelligent

transportation to green agriculture and e-health care.

Debasmit Banerjee et al. (2014) have presented a new approach to provide privacy for IoT

in an environment of multi trust domain. The idea behind this is to develop a new slotted

channel access mechanism for privacy aware using which IoT nodes from multiple type of

operators and trust domains may share given channel without exposing mutually their

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identities, thus new threats from cross trust domain traffic issues geared toward link layer

topology estimation, node profiling and node-tracking.

2.3 Reported works on general applications based on Wi-Fi

UdezeChidiebele et al. (2012) have proposed a GRID WLAN with high performance

hotspot solution and through OPNET modeler. It presents very efficient metrics for its

deployment in simulations. Analyzing the GRID WLAN access points, the simulation results

shows that with the specific design model, a carefully selecting buffer sizes, network

framework management with network load intensity and fragmentation threshold will provide

a very efficient hotspot solution. Bheemarjuna Reddy Tamma et al. (2009) have presented a

new approach for the application of the Cognitive Networking paradigm to the development of

autonomous Cognitive Access Point (CogAP) for wireless networks like home networks and

Wi-Fi hotspots. Such type of environments, AP per service provider/residence for providing

wireless services to the users is implemented. More number of APs from various service

providers and residences for specified bandwidth in any region and they can minimize the cost

of proposed autonomic network control by providing access point with a cognitive

functionality.

David Blinn et al. (2005) presented the new approach of 802.11 hotspot network. Five

weeks of SNMP traces have examined from the Verizon Wi-Fi Hotspot in Manhattan and

more number of users may access infrequently the specific network but have found out that

hourly, daily and weekly.Utilization capability of AP was not even and some unusual type of

patterns in traffic load is displayed in the wireless network. But some of the characteristics

were same to those observed previously in campus WLANs.

Anand Balachandran et al. (2003) observed that type and number of hotspot venues has

changed by mobile computing, there is remaining various deployment and technological

challenges before wireless hotspots may come into a ubiquitous infrastructure. The challenges

such as management, location services, authentication, security, coverage, interoperability and

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billing are included. They also have analyzedvarious existing research, the function of

standards bodies, and the working experience of commercial hotspot providers in the specific

areas, and described compelling open research questions that remain in detail.

OussamaStiti et al. (2014) have created a new architecture that is both flexible and

ergonomic in order to fulfill the need for client mobility and connection. NFC technology is

used as a radio channel for initiating communication with the wireless network. Virtual Wi-Fi

AP will be instantiated and all access certificates and policies for an authentication based on

EAP-TLS are distributed. The final result of new topology is to easily allow access to

specified services using a virtual Wi-Fi AP in a public hotspot with an enterprise-grade.

Yousef Daradkeh et al. (2014) have described a new model for delivering hyper-local data

for smart phone subscribers. Their new approach applies Wi-Fi proximity as a service.

According to this new concept, existing or a specially created Wi-Fi hot spot could then be

used as sensor that can easily trigger access for some of the user-generated information

snippets. In this research article they have presented more applications for deployment:

integration for proximity, context-aware browser and social streams and dynamics models for

human based on proximity data. As the possible events, they can easily mention, for example,

news and deals delivery in large malls, news feeds for office campuses and centers, Smart City

projects, social curation, personal classifieds, etc

Vitthal S Saptasagare (2014) has introduced novel concept of Li-Fi. The data through light

illumination of fiber optic by transmitting data through an LED bulb that continuously varies

in intensity much faster than the human eye can follow. D-LIGHT may produce data rates

faster than 10 megabits per second, which is higher speedthan general broadband connection.

If this new approach can be implemented into practical, every bulb can be designed with a Wi-

Fi hotspot to communicate wireless data and the greener, safer, cleaner and brighter future can

be obtained. The Li-Fi concept is attracting with great interest, because it can offer efficient

alternative and genuine to radio-based wireless network. As more number of people and their

devices access specific wireless internet, the airwaves may become clogged, making it very

much difficult to receive a reliable and high-speed signal. It may solve problems like the

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minimum use of radio-frequency bandwidth and also may allow internet where old radio

based wireless connection cannot be allowed such as hospitals or aircraft.

Stephan Haller (2010) tried to bring clear understanding about the important terms such as

devices, things, resources, entities of interest, identity, addressing and the relationships

between them as well as addressing, identification, resolution and discovery. The distinction

between the device and entity of interest has been shown. Implementing clear approach will

focus on the real research problems like connecting and interacting with a myriad of

heterogeneous devices and to deploy and also manage such type of infrastructures in the real

world. Solving these real problems become possible to reap the many possible benefits of the

IoT. Proposed systems may be applied in the health care, energy grid, supply chain

management, public safety or environmental management.

Nor Aida Mahiddin et al. (2013) proposed a new approach to calculate and find the

location of a specific user in indoor area using Wi-Fi signal strength with IEEE 802.11g

standard based on trilateration technique. Their research is based on the problem in order to

determine the position of a given object in inside a building or indoor environment. The

problems arise when the position of a selected object inside a building cannot be determined

using GPS. They have discussed the signal strengths percentage obtained from Wi-Fi analyzer

in a smart mobile phone were converted into distance between each AP and users. A user‟s

indoor environment position could be found out based on a formula proposed based on

trilateration technique.

2.3.1 Reported works on Wi-Fi with ZigBee

Sangsoon Lim et al. (2013) have presented a novel technique of Narrow Band Protection

scheme that addresses with interference problem between the cross-technology of Wi-Fi and

ZigBee. The NBP protector detects the ongoing ZigBee transmissions effectively with

lightweight overhead by the PHY layer correlation technique. Also it protects ZigBee packets

bursts using the correlation technique with the PN codebook. Theyhave also showed the

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feasibility of NBP by implementing this technique on the real GNU/USRP Radio

platform.Their simulation results show that ZigBee throughput is enhanced by NBP up to

1.77x when compared to the existing scheme.

Rakesh Manukonda and Suresh Nakkala (2015) have proposed the Wi-Fi-ZigBee wireless

gateway based on EMW-380 Wi-Fi module and STM32W108 RF chip may connect the

standard network with the ZigBee network seamlessly. Wireless gateway act as a sink in

ZigBee network, it receives information from sensor nodes and also interacts with them.

Wireless gateway can communicates with network servers or PC by means of AP in WLAN.

Both the software scheme and hardware scheme of the wireless gateway are introduced.

Performance of the wireless gateway is tested and it may be used for general purposes.

Performance and stability of wireless gateway suits the usual target of WSN application from

the result of performance test. Generally WSN application is small amount of data

transmission, low real time demand and low bandwidth.

Yepeng Ni et al. (2013) have taken S3C2440 microprocessor, ZigBee and Wi-Fi wireless

communication module to implement the wireless home gateway. This home gateway realizes

the advantage of ZigBee short-distance transmission and data transmission of Wi-Fi in remote

areas. It can able to convert ZigBee protocol data or Wi-Fi protocol data, and communicating

with them. From the simulation result of performance test they have analyzed and showed that

the stability and performance of wireless gateway may suit the general target of smart home

application.

Peizhong Yi et al. (2011) have evaluated performance of ZigBee under Wi-Fi interference

for applications like smart grid. They have introduced a theoretical model as well as

simulation model which accurately reflect the Wi-Fi and ZigBee coexistence natures using

MATLAB/Simulink. They have shown both analysis and simulation results of ZigBee and that

may be interfered severely by Wi-Fi and that a „Safe Offset Frequency‟ and „Safe Distance‟

can also be identified to guide easily ZigBee deployment. They have shown that distance of 8

m between Wi-Fi and ZigBee is a „safe‟ distance which can give the maximum reliable

ZigBee performance regardless of the offset frequency, while 8 MHz frequency is a „safe‟

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offset frequency even when the given distance is just 2 m. They have proved that ZigBee

provides better performance when the Wi-Fi interference is not significant in general cases.

Their proposed interference mitigation technique provides efficient means of obtaining

reliable data service in significant Wi-Fi interference.

YifanZhang and Qun Li (2012) have proposed a system, HoWiES that saves energy

consumption of Wi-Fi connections in mobile devices with the ZigBee radios assistance. The

main component of HoWiES is a ZigBee- Wi-Fi message delivery model that enables Wi-Fi

radios to inform various messages to ZigBee in mobile devices. Based on the ZigBee- Wi-Fi

message delivery model, they have designed three different protocols that target at three Wi-Fi

energy saving applications in scanning, standby as well as wakeup respectively. They also

have implemented the HoWiES system with any two different mobile devices platforms and

two different AP platforms and their real practical evaluation shows that their system can

easily inform thousands of various messages from Wi-Fi radios to ZigBee radios with an

accuracy of 98%, and their less energy consuming protocols, while maintaining the wakeup

delay to that of the given specified standard 802.11 power save mode, also save 85% and 88%

of energy consumed in standby state and scanning state respectively.

Erina Ferro and Francesco Potortì (2004) have described about the protocols Bluetooth

and Wi-Fi of wireless communication standards as well as distinguishing their main features

and behaviors in terms of different metrics such that including network topology, quality of

service support, capacity, security and power consumption rate. But the important parameters

like consumption of power, data transmission quality and security are new challenges for these

protocols because the technology is continuously updating in their standards and their

implementations. The authors‟ research areas include not only finding an accurate solution to

the new hidden terminal problem as well as supporting real-time transmissions and these

protocols can be surely mapped with the real-time traffic constraints into the client QoS

requirements. They have developed efficient routing algorithms in mobile device multihop

environments and increasing security of data transfer while maintaining easy access, reducing

interference and implementing new multiplexing approaches like UWB and MIMO.

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Pratibha Singh et al. (2011) have discussed the clear overall view of this state-of-the-art

Bluetooth technology. They have also described most of the real and current issues that should

be solved and that have been specified by the Bluetooth technology standards.This research

paper presented a tutorial for Bluetooth technology on the Java platform. The sample code

also demonstrated to develop Bluetooth-enabled devices for wireless applications. The

specified APIs enable to exploit the power of the Java programming fully to develop new

wireless applications in a standard way. This given set of APIs is a key enabler for Bluetooth

technology that will help software developers and software vendors tap the potentially highest

market for Bluetooth wireless technology.

VikethozoTsira and Gypsy Nandi (2014) have described some types of security related

measures that can be easily implemented during the period of data transmission using

Bluetooth technology. Also they have presented the intervention about the specific attacks on

the devices when it is connecting with another device during the data transmission using

Bluetooth technology. This research paper shows clearly about the different way of

implementing this new approach of Bluetooth technology to obtain best ways of

communication between specific devices. The researchers also discussed about various type of

information related to the specific Bluetooth system and as well as discussed most of the

applications of Bluetooth. Each and Every Bluetooth security personnel should have to

provide updates automatically to its all given security protocols and privacy protection

methods of particular user for every new security breach.

Javier Cubo et al. (2014) have presented a platform to manage the behavior-aware

orchestration of devices and integration as services accessed and stored via the cloud network

in ambient assisted living (AAL) applications. They have also described their new proposal of

modeling the heterogeneous devices as services by using the DPWS standard (Devices Profile

for Web Services which has been extended with the purpose of determining the order of the

sequence of exchanged messages and with the behavior specification of devices during their

composition). They have used a DPWS-compliant gateway and service-oriented environment

to orchestrate the specific devices according their behavior. They have also analyzed the

design and implementation of cloud-based IoT platform for accessing and monitoring the data

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in remotely, responding to critical and emergency conditions, which is a crucial problems in

AmI systems and validated the proposed approach in real scenarios to AAL application, an

emergency monitoring condition, to help medical personnel with the continuous health

monitoring of a more number of patients and data at real time, by devices and sensors

connected to the patient to detect and prevent any emergency condition both in the hospital

(local area) and at home (remote area). They have also discussed and demonstrated that the

cloud based solution for the management of specified systems. It allows user access and

handling demand elasticity simplified and effectively.

Serbulent Tozlu et al. (2012) have discussed the feasibility of very low-power Wi-Fi to

enable IP connectivity of battery-powered devices is studied with the specific three key

practical areas of concern: effect of interference, Power consumption and communication

range. Transmitting/receiving data and packet size have minimum impact on power

consumptionat high data rates. Retransmissions can affect energy consumption and this impact

is maximumfor low data rate operation. Their study shows that battery lifetime of a Wi-Fi

enabled sensor mainly depends on the operating environment. Whether or not it is required to

receive real time and timely command messages plays a main role in energy consumption,

since such type of operation requires frequent wakeups. Other operations such as periodic data

transmission, initialization/association, keep-alive messages and event triggered messages for

connection maintenance have lesser impact on power consumption, generally when high data

rates are used. The AP may become a bottleneck and affect the latency and reliability

considerably only under heavy in-network traffic. The specified communication range is

related to the data rate directly. Lower data rate may cover higher communication range and

maximum coverage area. Their experimental results clearly show that in a residential building,

a single AP operating at 1Mb/s, even though it is not installed in aproper and optimal location,

may provide full coverage for all sensor locations. It is desirable to operate at higher data rates

to achieve very low power consumption. So data rate selection may be a tradeoff between

battery lifetime and communication range. Thus, it is often recommended to operate at

maximum data rate at which the selected device is within the specified communication range

of AP.

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John A Stankovic and Charlottesville (2014) have discussed various future directions in

the research field of IoT (internet of things). Zanella et al. (2014) have focused to an urban

based IoT device and it is broad category. These general models are finalized by their specific

application domain. Urban IoTs are designed to implement the Smart City environment and it

aims at exploiting the advanced communication technologies to design added-value services.

This research paper mainly focuses a comprehensive study of the enabling new technologies,

architecture, protocols for an urban IoT for Padova Smart City project.

Shanzhi Chen et al. (2014) introduced the Internet of Things development in China, R&D

plans, including policies, standardization and applications. With the view of China's, they were

discussing some of the challenges on technologies, standardization and applications also have

proposed a general and an open IoT structure consisting of three different platforms to obtain

the architecture challenge.

ChayanSarkar et al. (2014) proposed a new Distributed Internet like Architecture for

Things (DIAT). They also proved that it will solve most of the problems in the large scale

expansion of IoT. It addresses generally heterogeneity of IoT, and also enables addition of

new things across most of the applications. They proposed a new approach of usage control

policy to support privacy and security in an environment of distributed nature and a new

layered architecture that provides different levels of abstraction to solve the problems like

heterogeneity, scalability, interoperability and security.

2.4 INFERENCE FROM LITERATURE REVIEW

From the works reported hitherto, communication between ZigBee nodes in various fields

like Home automation, Industry automation, Agricultural applications, security and power

saving applications are carried out in indoor as well as outdoor environment. Active research

work is limited to signal interferences within the closed indoor environment. Since signal may

be affected due to various reason like physical obstruction and any other building

configurations.The radios that will make Wi-Fi work are prone to interference. Microwave

30

ovens, Cell phones, walls, and metal like those that make up filing cabinets can interfere with

all Wi-Fi signals, giving unreliable network performance. In this research work,

Communication between IoT (Internet of Things) nodes is analyzed using mail concept based

on Wi-Fi protocol. Various performance metrics of Wi-Fi enabled mobile nodes are also

analyzed to offer reliable and efficient communication among the IoT nodes. IoT based

applications such as Smart parking slot, Weather reporting system, Smart irrigation and Air

pollution monitoring are implemented and tested successfully.