CHAPTER 1: INTRODUCTION
Mark Weiser is the father of Ubiquitous Computing. He is also the head of Ubiquitous Computing Project at PARC in 1988, at the Computer Science Lab at PARC where Mark worked. He also states his belief that UbiComp is the exact opposite of virtual reality. "Ubiquitous computing is roughly the opposite of virtual reality. Where virtual reality puts people inside a computer-generated world, ubiquitous computing forces the computer to live out here in the world with people. Virtual reality is mainly a horse power problem; ubiquitous computing is a very complicated integration of human factors, engineering, social sciences and computer science. Weiser states that ubiquitous computing, though currently using portable devices, does not mean that portable equals ubiquitous.
Nicholas Negroponte, inventor and director of the Media Lab at MIT. He is also credited with the start of the Ubiquitous Computing paradigm. His writings in the 1970's largely started a path to the way Weiser and others are implementing ubiquitous computing as a new paradigm.
Mark Weiser invented the idiom "ubiquitous computing" around 1988, during his term as Chief Technologist of the Xerox Palo Alto Research Center (PARC). He expresses the subject largely by defining the below topic. (ISTAG) The IST Advisory Group of the European Union had a vision of "Ambient Intelligence" (AmI) in 1999. It is "an exciting new paradigm of information technology.
Ubiquitous computing is a post -desk model of human-computer interaction in which data process has been incorporated in everyday activities and objects. Using ubiquitous computing enhances computational devices as well as systems. This model is measured in progression from the desktop paradigm. Ubiquitous computing has involved in many research topics such as mobile computing, human-computer interaction, distributed computing, artificial intelligence and sensor networks.
Ambient technology is embedded and invisible, we can place wherever we require, and it enables easy interactions, familiar to all our senses and adaptive to contexts and users. AmI planned a shift in computing who has all set of devices around us by providing users with intelligent conditions from traditional computer. It is "an exciting new paradigm of information technology, in which people are empowered through a digital environment that is aware of their presence and context sensitive, adaptive and responsive to their needs, habits, gestures and emotions". This paradigm is also said to be ambient intelligence or pervasive computing. If objects involved primarily then are mentioned as physical computing, ubiquitous computing was proposed in various aspects like applications and ubiquitous systems. 
According to Mark Weiser, ubiquitous computing is the method of enhancing computer use by making many computers available throughout the physical environment, but making them effectively invisible to the user.
According to Marcia Riley, Ubiquitous computing, or calm technology, is a paradigm shift where technology becomes virtually invisible in our lives.
Ubiquitous computing (UC) literally means "computers everywhere". The research schedule of, it does not contain every computer. The focus is in computers that the user uses in interacting with their environment. And also it is concerned with technology that is located between the users with the environment when these two things are in active interaction.
For the purposes of this scope of UC, two placeholders for it have been identified.
* Firstly, it can be found embedded in personal technology devices, such as cellular phones and wireless terminals.
* Secondly, it surround us in our environment attached and embedded in all types of objects ranging from books to buildings see figure 1:
A. Technology between the users and the environment in general case,
B. Personal technology near the user, and
C. Technology attached to the environment.
Also, increase the quantity of computers we utilize while interacting with the environment, ubiquitous computing, it also promotes a new type of use for these computers.
Two key concepts in recognizing this new type of usage are:
* Context awareness: it has been seen as one of the solutions for decrease information overload, in particular in relation with personal technology.
* Intelligent user interfaces: its an important part of smart environments, see figure 2:
The cause for highlight context awareness together with personal technology is the fact that with personal devices context awareness is possibly easier to know a user's personal preferences and use the increased awareness consequently.
In smart environments the user's preferences are not generally known and a most common approach for developing the interaction has to be used. 
Generic features of Ubiquitous Computing are:
* Transparent Interface
* Awareness of Context (s) and
* Capture Experience.
1.4.1 Transparent interface:
It is one of the important features of Ubicomp. It hides their presence from user. Its provide interaction between application and user. Such as speed recognition, free from pen interaction, gesture recognition, and computational perception.
It is most commonly used interfaces are keyboard and mouse. Its need varied interfaces that can provide same functionality and flexible interfaces. 
1.4.2 Awareness of context:
It environment should provide awareness information in a way that is adequate for the current situation of the user. The contexts itself rely on parameters such as the current type of co-operation, the current task, tools used and the artifacts. These are simple example of context is Time and Location.
It environment should also provide information about the context of origin of the awareness information, its mean context in which an event occurs hugely determines.
It environments should allow users to share awareness contexts. Users with shared interests should can share and exchange their awareness profiles.
Context aware application is one which can capture the context. It's according to change behavior. It needs applications that are context aware and permit rapid personalization of their services. 
1.4.3 Automated capture:
In Automated capture, our every day experience and make it accessible for future use. Its control multiple stream of information, time synchronization, correlation and integration
It needed automated tools that support capture, integration and future access of information. 
1.5 Basics and Factors of Ubiquitous Computing
It abbreviated to "ubicomp", refers to a new genre of computing in which the computer completely pervades the life of the user. In its computers become a helpful but invisible force. Supporting the user in meeting him or her necessitates without getting in the way.
The inventor of the term "ubiquitous computing", Xerox PARC's Mark Weiser (1998), described it this way: "... [Ubiquitous computing] highest ideal is to make a computer so fitting, so imbedded, so natural, that we use it without even thinking about it." 
Ubiquitous computing includes most areas of IT and achieving the vision will depend on several factors they are:
* Ubiquitous connectivity
* Interoperability (standards for devices and networks; identification; device and network discovery; self- configuring, seamless networks etc.)
* Improved intelligent interfaces (display technologies; natural interfaces; intelligent agents etc.)
* Miniaturization (sensors and wireless technologies and smaller or lower power processors.)
* Security and reliability (reliable, secure systems; and privacy features).
* Intelligent system (with sensor networks; location; semantic networks; context awareness; data handling; and search etc.) 
1.6 Elements of Ubiquitous Computing
Nanotechnology and Wireless Technology:
If computers are to be ubiquitously, unobtrusive, and truly helpful, they should be as small as potential and capable of communicating between themselves. Technological movements supporting these goals are:
* Wireless computing
The tendency to miniaturization of computer components down to an atomic scale is known as nanotechnology. It involves building highly miniaturized computers from individual molecules or atoms acting as transistors, it is heart of the computer chip.
Its extreme miniaturization of transistors allows for inspiring levels of computing power to be put into tiny packages, which can then be unobtrusively tucked away. 
Ø It refers to the use of wireless technology to connect computers to a network.
Ø It is so attractive
Ø Wire computing allows workers to escape the bind of a network cable and access network and communication services from anyplace in reach of a wireless network.
Ø It has attracted enormous market interest. 
Context-Awareness and Natural Interaction:
Small computers that communicate wirelessly provide a needed infrastructure for ubiquitous computing, it movement aims to make computer easier to use and more helpful. In fact, computers must be able to correctly expect the user's needs and accommodate her or him natural communication style and modes. 
These themes are captured in the ubiquitous computing movement's focus on:
Ø Context-aware computing.
Ø Natural interaction.
Ø It promises is that computers will be capable of understand sufficient of a user's current situation to offer resources, services, or information related to the particular context.
Ø The attributes of context to a particular situation vary widely; include the affective state, past activity, user's location, and current role (mother, office manager, soccer coach, etc.).
Ø Context may also include the current time and date, and people in the environment and other objects.
Ø Context- aware systems must help filter information and make IT work for us without us having to actively interrogate systems. This permits learners to focus on the task rather then the technology. 
According to Donald Norman, said that he doesn't want a word processor; he wants a letter writer-something that will allow him to get the job done of writing a letter, without the instrument getting in the way.
Ø It is for the computer to supply resources, services, or information to a user.
Ø As a result, the user is not distant with the dual tasks of using the computer and getting the resources, services, or information. 
CHAPTER 2: Types and Development of Ubiquitous Computing
Ubiquitous computing can take different types. They are:
1. Portable computing
2. Pervasive computing
3. Calm computing
4. Wearable computing
2.1 Portable computing:
It made computers likes handheld and Laptops, which you can carry, your computer everywhere, but your experience is only slightly different than in your office-you still should interact with the computer through a more or less traditional interface.
It comes in three varieties:
* Subnotebook and
In portable computing, different sized devices are matched. It will include Network Computers where, by plugging into a phone line or the Internet. 
2.2 Pervasive computing:
Pervasive computing is the third wave of computing technologies. Pervasive computing initially called ubiquitous computing age: one person, many computers. Millions of computers embedded in the environment, allowing technology to recede into the background.
It is a rapidly developing area of Information and Communications Technology (ICT).and it also the increasing integration of ICT into people's lives and environments, made potential by the growing availability of microprocessors with inbuilt communications facilities. It has many possible applications, from health and home care to environmental monitoring and intelligent transport systems.
Pervasive computing is expected to develop to include more traditional appliances such as refrigerators, toasters, ovens, home security systems, washing machines. 
2.3 Calm computing:
It is one of the types in ubiquitous computing. Weiser (Author) became more interested in a vision of Ubicomp he called Calm Technology or Calm Computing. Author noted whereas computers and games for personal use have focused on the excitement of interaction, when computers are all around, we interact with them differently. Calm computing e.g." dangling string" network monitor.
Frequently, we want to compute while doing something else. The term 'periphery' refers to what we are attuned to without attending to explicitly. This is akin to foreground processing and attention versus background processing and attention. Things in the periphery are attuned to by the great portion of our brains dedicated to peripheral processing. 
* Ubiquitous computing is closely related to "calm technology."
* Calm technology is concerned with making technology truly support a user; give them a sense of control (possibly in spite of a range of devices and gadgets that may become overwhelming, even when "hidden" in cupboards and in domestic appliances).
* It envisions a world where computers do not cause stress, but improve our lives and make many tasks easier: they do not distract, but remain unobtrusive, assisting with a task, not being the focus on the task.
* It has greatest strength, therefore, fabrication in the fact that computers are made to conform to their users, and not the other way around. Information is offered in the manner that a user decides, and is easily reachable.
* A user does not feel slowed down or distracted by using this Calm technology.
* Weiser and Brown (1995) inform us that "Designs that encalm and inform meet two human needs not usually met together. Information technology is more often the enemy of calm: pagers, news services, cell -phones, e-mail, the World Wide Web, TV, and radio bombard us frenetically."
* Calm technology with ubiquitous computing is set to make an interesting future for an ICT and AI technologies in augmenting the real world. 
Calm technologies are said to calm us as they can allow our periphery in three ways:
ü To engage both the centre of our locus of attention and the periphery of our attention, which moves back and forth between the two;
ü To enhance our peripheral reach by bringing more details into the periphery. It informs without overburdening us. It has a higher capacity for storage than at the centre of attention.
ü To offer locatedness (location-awareness): when our periphery is functioning well, we are tuned into what is happening around us, and also to what is going to happen, and what has just happened. We are connected effortlessly to a myriad of familiar detail. 
2.4 Wearable computing:
Wearable computing facilitates a new form of human--computer interaction comprising a small body--worn computer such as user--programmable device that is always on and always ready and accessible. Incidentally, the new computational framework differs from that of hand held devices, laptop computers and personal digital assistants (PDAs). The "always ready" ability leads to a new form of synergy between human and computer, characterized by durable adaptation through constancy of user--interface.
It is a type of "extension" of your body that allows you to perform "extraordinary" tasks. Using only your body when something that you never could do. It is like becoming a "super-hero": you can be in over one place at the same time. Wearable computing researchers have revealed ubiquity. 
Operational modes of wearable computing:
Three operational modes interaction between human and computer there are:
* Augmentation and
* Mediation. 
The six attributes (six signal paths) of wearable computing:
In wearable computing, six informational flow paths related with this new human--machine synergy. There are:
Ø Unmonopolizing of the user's attention.
Ø Unrestrictive to the user (mobile, roving, ambulatory, "you can do other things while using it'', for example: you can type while jogging, etc.)
Ø Observable by the user
Ø Controllable by the user
Ø Attentive to the environment
Ø Communication to others 
It is changing our daily activities in a variety of ways. When ubiquitous computing comes to using today's digital tools user have a tendency to
* be more active
* communication in different ways
* have more control
* use and consider temporal spaces and geographical differently 
More, ubiquitous computing is
* visible and invisible
* local and global
* personal and social
* private and public
* an characteristic of both information dissemination and knowledge creation 
Ø Wireless networking wants to be developed to accommodate remote computers "hiding" in our environment.
Ø To develop infrared pens which depend on a camera-like device behind the screen to sense the pen position?
Ø Interface and computer design had historically been aiming to make computers more "dramatic", so interesting and exciting to use. 
2.7 Application development:
It using the low-level API, they identified six patterns that were required for all applications:
2. User centrism
3. Multi-device utilization
5. Run-time adaptation and
6. Ubiquitous computing environment independence.
As a result, they provided application development and management support modified to ubiquitous computing environment that automated the above mentioned patterns.
Some application increased such as they detected the need to combine the behavior of different applications, so they built a ticker tape that uses multiple displays synchronously, and also they found that it possible useful to use it to display information generated by other application. 
2.7.1 Rapid development cycle:
Ø Our computer provides a complete supporting infrastructure for rapid development of ubiquitous computing applications.
Ø Involving Mechanisms for controlling the inter-application behavior.
Ø There were able to identify an application suite rapid prototype development cycle. as shown figure 1:
Ubiquitous computing environments are extremely dynamic systems with ever changing requirements and constantly refined specifications. As a result, a prototype-based development cycle is most appropriate to cope with new demands. They are four stages:
1. In First stage, our development cycle identifies the initial set of functionality and behavior for the scenario.
2. In second stage, the higher-level services of our system allow the rapid development of the tools that help in achieving the functionality wanted. And also include writing composing existing application or new application in special ways.
3. In third stage, the new tools are installed in the test-bed environment and uses of the tools is appraise based on users' use and reactions.
4. In fourth stage, requirements and specifications are refined based on the appraisal step and an improved prototype is developed by going back to second stage.
The mainly profound technologies are those that vanish. They weave themselves into the fabric of everyday life until they are indistinguishable from it, said by Mark Weiser. They are three waves: 
Three waves of computing:
* Mainframe wave: it age when many people shared one computer.
* Personal computer (PC): it wave when single person has one computer.
* Ubiquitous computing: moving to the ubiquitous computing wave one person shares many computers. Now-a-days, internet age is seen as a transitional phase between the ubiquitous computing waves and personal computer. 
Key elements of ubiquitous computing:
* Devices, or
* Objects, or
In its environment require are:
In sequence for devices and objects to use become part of information sharing network, wider intelligent, it is vital that every one have a unique identity.
Here, using two important technologies to provide identity are:
* Radio Frequency Identification (RFID) tags.
* Visual barcodes.
The capability of devices and objects to have location information adds another important level of intelligence allows the discovery of objects, resource and people and also allows location supported tools and services.
It ability can give computer 'eyes and ears' creating intelligent network that be able to collect a range of a data and also respond to events.
Wireless connectivity is allowing ubiquitous computing, but the increasing range of technologies. 
These technologies have approaches of use that can be:
* Explicit: it interactions are those where aware action by a user enables an interaction.
* Implicit: it interactions are automatic also be able to happen not including any direct user intervention. 
Our opportunities for explicit interactions with the real world are increasing, but it is the implicit invisible interactions that will offer a real shift in how we sue and gain benefit from computer systems. 
CHAPTER 3: DESIGN AND TECHNOLOGIES
It is about finding solutions. Regrettably, not knowing how others previously applied a solution or why they did things a certain way makes it difficult to use again prior design knowledge. Consequently, designers-whether they are software engineers, Web designers, or architects-often end up having to reinvent the wheel. Because they are neither too general nor too specific,
It offers a solution to the difficult problem of reusing prior design knowledge.
They are written to be flexible enough for reuse in many situations, and designers can use them to identify and to plan for solutions recurring problems. We plan that such patterns also recommend an effective way to communicate solutions to ubiquitous computing design problems. 
3.1 Ubicomp design patterns:
Next, step in the evolution of design patterns is to apply them in a more determining field such as ubiquitous computing by documenting lessons already learned in this new field or that can be carried over from previous design knowledge.
Some of the ubiquitous computing patterns we have brainstormed include are:
* Physical-Virtual Associations,
* Global Data,
* Follow-Me Display,
* Context-Sensitive I/O,
* Anticipation, and
* Appropriate Levels of Attention. 
Above patterns, some focus on system aspects, some on user interfaces, and some on both.
3.1.1 Context-Sensitive I/O:
One design pattern we have developed that clues at what an ultimate ubiquitous computing pattern language may be like addresses the following problem:
* Ubiquitous computing devices will be use in a diversity of locations and situations, but the device interfaces should not interrupt or divert the user from performing a primary task or irritate a nearby group of people.
Because certain input and output modalities are more suitable in different situation, applying the design-pattern concept to this problem might yield the following solution:
* Input and output modalities should adjust to the user's current context.
For instance, depending on audio or output is not a good idea when the user is participating in a movie theater, in a meeting, or attending a lecture.
As Figure 2 shows, a context-sensitive cell phone must know when its owner is in a meeting and switch automatically to a vibration alert rather than require the owner to turn off the audible ringer.
Conversely, direct manipulation input to a handheld device can be inferior to pushing a few physical buttons or speech when the user is driving a car. Similarly, when the driver places or receives a call, the car stereo system volume must be lower automatically. 
3.1.2 Physical-Virtual Associations:
Another ubiquitous computing design pattern we have developed addresses the following problem:
* When people work together in some way, they should not have to spend more time configuring their devices.
For instance, at a meeting, the appropriate files, including biographies and contact information, have to appear automatically on every person's PDA or laptop. The following solution would apply to this problem:
* When users are near one another, make it easy for their devices to connect and create an association that lets them share information over the life of a session.
A Context-Sensitive I/O device provides the suitable output for making a Physical-Virtual Association. Some associations be able to occur automatically when two known devices come into physical proximity-such as, a user's PC and PDA could synchronize automatically.
As Figure 3 shows, creating other associations may require direct user action-for instance, letting others in the same meeting see documents on a PDA may require the owner's authorization. In other situation, users can connect their devices to create an association that permits them to share information in excess of the life of a session.
For instance, the Hummingbird launch a virtual connection between close to users skiing at the same resort, enabling them to track one another's location on the slopes and thereby communicate more easily. 
3.2 Design Principle:
Through it make easy data collection in the field. Represent in features of three ubiquitous applications they are:
* Probe ware
* Cyber Tracker
* Wise Palm Application
* It includes Concord Consortium Probes (CCProbes), interfaces, sensors, supporting software, and related curricula for classroom lab activities
* Concord Consortium Probes are used by students to heighten their understanding of the world including concepts related to force, temperature, current, motion and light.
* Concord Consortium Probes combine measurement with the computer's capability to record, display, and communicate visualizations of the measured data.
BioKids Research Group Nancy Songer, U Michigan
* It searches how organisms meet fundamental needs and how the environment supports a variety of organisms.
* Students use Cyber Tracker software on Visors to collect data and to answer: Which zone in my schoolyard has the highest biodiversity?
* Students upload data to a database to analyze animal richness, animal abundance. Cyber tracker and the database share common organizational structures to easily permit students to locate and analyze related data.
As figure 2 shows,
Wise Palm Application:
* Palm application integrated with the WISE Ocean Stewards project and visits to the Monterey Bay Aquarium
* Students collect data on fish at the Aquarium
* Data collection scaffold with multiple choice lists, designed prompts, hints, pictures of relevant objects, and opportunities for recording reflections. 
Design Principle Support the use of multiple representations of phenomenon.
Represented in features of three ubiquitous applications:
Ø Probe ware
Ø Net Calc
* It is a simplified drawing program for Palm handhelds with an animation tool that permits students to create dynamic representations of science phenomena.
* The animation tool consists of three components:
1. Create multiple pages
2. Duplicate pages,
3. Play pictures in succession.
* Students use animation to demonstrate understanding of polluted v. clean water and air and to show differences in virus and bacteria growth.
* Month long SimCalc curriculum adapted to Palm handhelds
* Representing the mathematics of change
* Graphical representations linked to (car) motion simulations 
3.3 ESSENTIAL TECHNOLOGIES FOR UBICOMP
3.3.1 Hardware Technologies:
In ubiquitous computing, required hardware technologies such as processors, memories, sensors, network (wireless), actuators, packing and integration, power and new technologies likes biomaterials, optoelectronics.
3.3.2 Software Technology
It also required software technologies such as operating environments, networking, middle ware, platform technologies and user interfaces.
It progress is slowly, most likely from 2008 we still using the same basic environments as today:
ü MS Operating System (OS), Linux, Symbian OS (?)
ü C++, Java, Scripting language (Python) and so on
ü Possibly some higher-level tools derived from Web Services technologies or XML
Programming will become a bottleneck, even more than nowadays:
* Reliability, fault tolerance: present programming models lead to spaghetti code
* Dealing with complexity: zero configuration
We are likely to require a variety of networking technologies also in the future:
Ø Wide area: large coverage, modest capacity
Ø Proximity: small coverage, larger (but still modest) capacity
Ø Personal or body area
Ø Perhaps also one-way broadcasting through digital TV
So multi access networking is required, with all its intrinsic complexities
* Roaming from one technology to another
* Multi homing? Congestion control? Multicast? etc.
* Mobility & identity management
* Trust establishment and management
Standards are nice, but how interoperable are they? How much complexity can be managed? 
Middle ware: 
SENSING IN UBIQUITOUS COMPUTING
From Personal Computer to 'Smart Devices'
* More applied than 'information appliance'
* Less CPU power, memory, UI
* more networking " the real power of the concept does not come from any one of these devices; it emerges from the interaction"
* more physical I/O " if a computer merely knows what room it is in, it can adapt its behaviour....without even a hint of AI" 
CHAPTER 4: ARCHITECTURES:
4.1 Thin Client Based User Terminal Architecture for Ubiquitous Computing Environment
Assumed Ubiquitous Computing Environment:
Ubiquitous computing environment assumed, see Figure 1 demonstrate. In this environment, computing devices in cyber-space capture the real-space from RFID tags as detected by tag readers.
RFID tags are attached to train stations, major buildings, and intersections. Each RFID tag stores just a unique identifier. Tag readers collect the IDs of the RFID tags in their range, and forward this information to the computing devices (hereafter called server) via the Internet and /or mobile communication networks. The server passes the ID to an information database, and retrieves information (name, color, role, owner, and other attributes) of the object. The server infers the user's surroundings from the collected information and offers various ubiquitous services as appropriate. 
User Terminal Requirement for the Assumed Environment:
In the ubiquitous computing environment assumed, every user must carry her/his user terminal in order to satisfy the following requirements.
1. Platform for the portable tag reader:
In order to control the portable tag reader, collect the tag information, and transfer the information via the mobile communication network, some kind of platform is required. In the assumed environment, the user terminal acts as this platform.
2. Subordinate control for the server:
It is difficult to provide the service that the user desires all of the time even if the server perceives the surrounding from a huge amount of information and an advanced inference engine is used. As a result, it is necessary to provide a service evaluation function, and feed the user's feeling back to the server. The user terminal should offer support functions to achieve these goals.
3. Actuation function:
In the order of the ubiquitous service to reach the user, the mechanism of service actuation is required. If shared terminals and robots, etc. are used as the actuator, information related to the user's privacy and security will be leaked in public spaces. As a result, the user's terminal must become an exclusive actuator that provides adequate privacy. 
General Requirement for the User Terminal:
The user terminal is needed in the environment considered here. In the general requirements for the user terminal are:
Ø Portability: Because every user always has to carry the user terminal, it must be light and small.
Ø Low power consumption: Because the user terminal should always be active when the ubiquitous service is required, it must have low power consumption and must run for long periods without battery change.
Ø Low cost: To be a fundamental requirement for each user. 
Thin Client Based User Terminal:
As described above, existing research does not satisfy the requirements for the user terminal in the assumed environment. According to authors plan the thin client based user terminal; it is light, small, and low cost terminal such as cellular phone that realizes RFID-based surrounding perception and acts as the actuator for the ubiquitous services. 
The thin client is an architecture that concentrates execution, storing, and management of the application on the server, and the client function is limited to Human Machine Interface (HMI) and some part of I/O. As a result, a simple terminal can realize the functions and the performance of a Personal Computer (PC). Particular, previous research, called mobile thin client, introduced a cellular phone-based thin client system that enables PC application such as Excel, Word, and Power Point, to be use through cellular phone.
The authors extended the mobile thin client to realize a cellular phone-based user terminal. Figure 2 demonstrate the architecture of the proposed user terminal. The HMI function for controlling likes correct, start, terminate, selection of critical choices, server ubiquitous service is simply inherited from the mobile thin client. All other functions such as attached portable type tag reader, collecting the RFIDs function, and actuator control functions likes vibration, BEEF, backlight blinking, and messaging to the user through the display of the cellular phone are extensions. The collected RFIDs are transferred to the server through the mobile communication network. The server retrieves the information about the objects from the information database, perceives the user's surroundings from this information, and generates actuator control instructions for the cellular phone. Also, the proposed architecture offers the function of continuing the ubiquitous services even when the mobile communication network is temporarily disconnected, this mechanism called event caching. 
4.2 Based on Web Services Architecture
The architecture is based on Web Service, it work on the assumption that the functionality made available by the system will be exposed as a service. The proposed architecture is presented in the following Figure 2
New ubiquitous computing applications can be built on this architecture. In addition, it can be implemented over any existing ubiquitous computing architecture. It is primarily composed of two major components based on two aspects. They are:
Ø The first aspect is related to the fact that web services are a way to expose internal operations so that they can be invoked through the web. Such an implementation requires the system to can receive requests through the web and to pass them to the underlying system.
In doing this, the problems are similar to those encountered in conventional middleware. We will refer to such an infrastructure as internal middleware.
Correspondingly, we will use the term internal architecture to refer to the organization and structure of the internal middleware.
Ø The other aspect of the architecture is represented by the middleware infrastructure whose purpose is to integrate different web services. We will refer to such an infrastructure as external middleware. Correspondingly, we will use the term external architecture to refer to the organization and structure of the external middleware. 
4.2.1 Internal Architecture:
The easiest way to understand the internal architecture is to analysis it as yet another tier on top of the other tiers of the enterprise architecture. Conventional middleware is used to build multi-tier architectures. In these architectures, individual applications or programs are hidden behind service abstractions that are combined into higher order programs or applications by using the functionality provided by the underlying middleware.
As a result, higher order programs can in turn be hidden behind new service abstractions and can be used as building blocks for new services. Because the composition of service abstractions can be repeated artlessly, the result is a multi-tier system in which services are implemented a top other services and basic programs. When multiple middleware requests are loaded on top of each other, the middleware used at every level does not need to be the equal. The important point is to have compatible service abstractions or to make them compatible using wrappers. The middleware simply acts as the glue necessary to make all the components in a given level interact with each other to form services that can be used by clients or higher levels in the hierarchy. 
Although it is not strictly necessary, usually the basic components of each middleware instance reside on a Local Area Network (LAN) and the resulting application also runs on the same LAN. Web services or, better, the technologies supporting web services, play the same role as conventional middleware, but on a different scale. The basis for composition is service abstractions very similar in nature to those used in conventional middleware, so that implementing a web service essentially requires an extra tier on top of the others to enable access using standard web services protocols. The following Figure 4 shows a typical example of such an internal architecture. 
4.2.2 External Architecture:
In this architecture have three main components. They are:
* Centralized brokers
* Protocol infrastructure
* Service composition infrastructure
220.127.116.11 Centralized brokers:
These are similar to the centralized components in conventional middleware that route messages and provide properties to the interactions for example logging, name and directory services, transactional guarantees, and reliability. However, as we will see, in practice the name and directory server is often the only centralized component present in Web service based architecture.
18.104.22.168 Protocol infrastructure:
It is refers to the set of components that synchronize the interactions among Web services and, particularly, implement the P2P protocols whose aim is to provide middleware properties in those B2B settings where a centralized middleware platform cannot be put in position caused by trust and privacy issues.
22.214.171.124 Service composition infrastructure:
It is refers to the set of tools that support the definition and execution of composite services.
Here, discussed until now is connected to wrapping internal functionality as a Web service, and not to integrating these 'wrappers'. This aspect, which was addressed by message brokers and workflow management systems in conventional middleware, must be the job of the external middleware. 
There are two solutions to this problem:
ü One is to implement the middleware as a P2P system where all members cooperate to provide name and directory services. Abstractly, this is a very appealing approach; but it is not obvious how to provide the degree of reliability and trustworthiness required in industrial strength systems.
ü Other solution is brokers acting or intermediaries as the necessary middleware. 
4.3.3 Privacy-preserving UBICOMP architecture:
Provide the Ubiquitous Computing environment and the use of privacy policies to protect a data sharer's privacy; the requirements of the architecture are as follows:
1) First provide the ubiquitous computing environment .The devices in this environment are assumed to be able of performing the tasks recognized to devices below.
2) The use of privacy policies.
3) Previous to using a UBICOMP device to share or observe data, the user logs into the device and identifies her.
4) Information regarding which data observers are online can be called up at any time on any ubiquitous computing device.
5) After logging in and previous to sharing data, the data sharer performs the following steps:
a) Requests to see which data observers are online.
The system will automatically request the requisite data observer policies and check for policy matching or compatibility; for every pair of policies contrasted, the system optionally permits the sharer to negotiate with the observer if the policies do not match. For each match, the system automatically sets up a connection to the data observer with the matching policy for data sharing. Once the data sharing session is completed, the system automatically tears down the associated connections.
7) A user who is both a data observer and a data sharer does both of the prior two items for data observers and data sharers. 
4.3.4 Architecture design
Here, describes the design of the privacy preserving UBICOMP architecture to satisfy the above requirements.
The design has the following components:
I. Global and Local networking (as shown in Figure 1),
II. A Privacy Controller ,(for every local network) and
III. Interfaces (to connect between every local device and the Privacy Controller). 
IV. Global and Local networking (as shown in Figure 1),
V. A Privacy Controller ,(for every local network) and
VI. Interfaces (to connect between every local device and the Privacy Controller). 
VII. Global and Local networking (as shown in Figure 1),
VIII. A Privacy Controller ,(for every local network) and
IX. Interfaces (to connect between every local device and the Privacy Controller). 
The description of each component follows.
126.96.36.199 Local and global networking:
These are assumed to be what is most commonly accessible, that is:
ü For local IrDA, Bluetooth, Ethernet, or Wi-Fi, and
ü For global Internet
The connection of local networks to the Internet is also supposed to be standard. 
188.8.131.52 Privacy Controller:
This component has the following functions:
c) Data sharing between data sharers and data observers who have matching privacy policies to sets up connections. Tears down the connections once the connected sharing sessions are completed. Through Link Module (LM) in the Privacy Controller, this function is performed.
See below Figure 4 illustrates the planned privacy-preserving UBICOMP architecture. It can be easily seen that, it is a hybrid architecture that is globally peer-to-peer, with peer nodes being the local networks, but within each local network, the Ubiquitous computing devices are centralized to the Privacy Controller.
The behaviors of the Policy Module (PM) and Link Module (LM), these are components of the Privacy Controller are illustrated by the high level state machines in Figure 5,the Compliance Module (CM) is external the scope of this work.
The arrows in Figure 5 are labeled using the convention "action or condition". Additional,
The symbols are:
* "?" stands for "received" and
* "!" stands for "send".
Suppose, if there is no match, the sharer has the choice to negotiate with the observer.
Ø To determine allow the mismatch or the mismatch to stand in which case the Policy Module ensue to process the next observer's policy. If negotiation is chosen and succeeds, the resulting match is registered and the Link Module (LM) is notified as previously mentioned.
Ø If negotiation is chosen and fails, the mismatch has to stand and the Policy Module (PM) ensue to process the next observer's policy.
In above Figure 5 (b), upon receiving policy match information from the Policy Module (PM), the Link Module (LM) ensue to use the match information to set up a connection between the data sharer and the matching data observer. Once the connection is set up, the Link Module (LM) notifies the sharer and the observer that they are connected and the sharer's session with observers can first observer connected (begin) or other observers already connected (continue). Upon receiving a signal from the sharer's device that the session has completed, the Link Module (LM) tears down all related connections.
Above Figure 6 presents a message sequence chart is showing the interactions between a data sharer, the Policy Module (PM), the Link Module (LM), and a data observer, in these components only one is shown for simplicity for the period between the points when a data sharer logs in to the point when she has finished her data sharing session. The scenario represented is for a first time successful policies match. 
CHAPTER 5: SECURITY FOR UBIQUITOUS COMPUTING
Ubicomp (Ubiquitous computing) is about networked microprocessors embedded in everyday objects like's home appliances, cell phones and also bookshelves, books, bathtubs and bus stop. This future is closer than you may imagine.
The insecurity of networked personal computers (PCs) is notorious. If we deployed ubiquitous computing as vulnerable as PCs, the risks for society would be catastrophic. In accessible style, how can we do better and identify the new problems?
Here, in this description presents a coherent framework to make sense of the many issues possibility.
Ø A readable basic coverage on security and cryptology.
Ø A primer to state of the art in ubiquitous computing research.
Ø An extensively annotated bibliography.
Ø A deeply discussion of specific, cutting-edge solutions.
Ø Ad-hoc networking and "peer-to-peer".
Ø A new technical treatment of ubiquitous computing security, including 802.11 and Bluetooth.
Security for ubiquitous computing combines brevity, authority and clarity. It will appeal to researchers and developers in ubiquitous computing, ad-hoc networking, and wearable computing, wireless and related areas. Because it is self-contained and readable, it will also establish analysts, technology watchers, valuable to managers and end users who want to understand the new opportunities and risks of ubiquitous computing (UC): 
* It refers to computers embedded in every day devices communicating with each other over ad-hoc wireless networks
* Focuses on Security and ad-hoc wireless networking
* Covers security issues for widely and well-established use technologies for examples are Bluetooth, IP and GSM
* Explain the security issues in "peer-to-peer networking," a current technology that is gaining importance in the media with applications for example ICQ Chat and Napster
5.1 Network Access and Security Issues in Ubiquitous Computing:
Here, Upkar Varshney (author) discusses some topics likes are wireless and mobile infrastructure, security, applications and services, and mobile payments. As a result of our current expertise and interest, author likes to concentrate on infrastructure and security issues and how problems of access, roaming, end-to-end security, coverage, location management, reliability and multicast communications could be addressed in the ubiquitous and pervasive computing environment.
According to IBM's definition of Pervasive Computing, is that "Convenient access, through a new class of appliances. To related information with the capability to easily take action on it when and where you require to".
5.1.1 Wireless and Mobile Infrastructure:
In ubiquitous and pervasive computing environment, many major issues related to wireless and mobile infrastructure. As infrastructure play a most important role in how users are able to interact with ubiquitous application and services. Their requirement is universal access or integrated to different wireless and mobile networks and it support for reliable communications, multicast (group communication) and inter-working of these technologies. Some of these issues have not been addressed and these should be covered before the vision of ubiquitous computing (UC) is realized.
Presently, there are some different types of wireless and mobile networks available now and between each type there are multiple standards such as CDMA, wire LANs, it also differ in coverage and access protocols. In wireless and mobile networks, multiple standards make interoperability very difficult and also limit the roaming between networks and decelerate the development of new features. It proposed solutions such as a world wide common standard for terrestrial wireless services.
Author suggests some possible architecture that would allow users to seamlessly roam across heterogeneous wireless networks. One of these architectures is based on a virtual overlay network with universal access points (UAPs); it is translate the network protocols into a generic protocol for a user device. (See below Figure 1).
This architecture supports highly dependable wireless operation where the existence of multiple heterogeneous wireless networks, it's also very transparent to users. These universal Access Points (UAPs) will also translate frequency and QoS schemes used in wireless networks that are currently being accessed by users.
Another, architecture is by having an intelligent network card that can switch between two or more different wireless networks. Intelligent network card are expected to increase coverage. It provides dependable access and will propose an integrated access to mobile and wireless networks with several possibility of quality of service to users.
Most users don't need to know what networks they are presently accessing in ubiquitous environment. So that author focus is on personalization and services and not so much on the infrastructure. The devices, applications and software have to move across multiple heterogeneous wireless networks effortlessly without making these transitions apparent to users.
Infrastructure issues in the ubiquitous environment are:
* No difficulty of use to registration at hot-spots, easier setup,
* New network management tools for improved performance such as access, interference, and security management functions,
* Creation of a localized attractive environment for customers,
* Creating personalized and localized environment (like games for kids while parent shop, local maps, areas of interest, location-sensitive advertising, coupons for nearby restaurants and shops, etc.),
* Support for push and pull applications, multicast and broadcast of information for example advertisements or game score information), and
* Support for transactions even when the user is going through brief intermittent connectivity or disconnectivity 
5.1.2 Security Issues:
In ubiquitous and pervasive computing major security issue are individual, groups, and organizations. In wireless and mobile infrastructure stems from both the use of multiple "incompatible" security schemes and due to "inherent" weaknesses in certain wireless security algorithm for example wireless LANs.
In the ubiquitous environment several security issues including they are:
* Non-repudiation, and
Other issues would include convenience, speed, ease-of-use, and standardization. Depending on the type of data and the cost of possible loss, modification, and stolen data, a security strategy must be devised and implemented. 
Additionally to security and privacy risks, new vulnerabilities occur because of use of wireless devices. Use of wireless infrastructure may involve multiple wireless networks with different levels of security. These cause possible change/deletion of information, and rejection of service. In addition to these, many more security issues arise due to poor implementation, feature interactions, unplanned growth and new flaws that are created due to prior attacks (Figure 2).
The end-to-end is one of most important security issues in ubiquitous environment as devices, application, software and multiple networks will exist and inter-operate. The security issues can be addressed through mobile middleware. For example, WAP provides security using Wireless Transport Security Layer (WTSL), but it does not always result in the end-to-end security only between on WAP gateway and device. 
5.2 Secure zero configurations in a ubiquitous computing environment:
Zero configurations networking:
It is required for environments where administration is not possible or not practical. In general, most of the users are non-experts and no skilled administrator is present. Also, the number of interconnected devices can be hundreds or even thousands. Lack of centralized administrator and server, the probable require for manual management, and the increasing number of devices in a ubiquitous environment means that zero configurations is a greatly desirable goal.
Zero configurations in ubiquitous computing (UC):
In a Ubiquitous computing environment, our goal is that, a device can dynamically join a network, automatically take an IP address and other configurations parameters, broadcast its capabilities, and learn about the attendance and capabilities of other devices.
Transfer a unique address to every device in a network is a requirement for connection in the network, and is the first important parameter that should be configured to allow association as a host in a network.
IPv6 Stateless Address Auto configuration (IPv6 SAA) allows a host to connect to a network, configure an address and start communicating with other nodes without authenticating itself or ever registering, it based on, some protocols have been proposed for IP address auto configuration in ad hoc networks. Other protocols could be proposed in the future for different scenarios in a ubiquitous environment.
But, the goal of all these protocols remains the same: devices should be configured automatically and be connected to the network without any user intervention or centralized servers.
After connecting to a network, a device must be capable to automatically detect the services supplied through other devices in the network and use them, and also when services become unavailable. Service discovery protocols must not require service discovery servers, user administration, or prior configuration to be effective in a ubiquitous environment, its characterized by a heterogeneous mix of services and technologies, and rapid growth of the number of devices; particularly, future applications may require developing services across multiple service locations at the same time. Hence service discovery protocols should also address issues of interoperability and scalability of heterogeneous devices. 
5.2.1 Security issues:
If we desire to use zero configurations in a ubiquitous computing environment a number of serious security issues should be addressed. Author briefly consideration some of the key such issues:
184.108.40.206 Wireless networking:
It is widely used in the ubiquitous environment. Wireless links are vulnerable to both active and passive attacks, for example denial-of-service and eavesdropping attacks. Potential damage includes interfering with messages, impersonating nodes and compromise of transmitted secret information. Limited bandwidth of wireless connections also gives a target for denial-of-service attacks.
It used for ubiquitous computing are different and several; some are possible to have limited physical protection, and most possible to be compromise, hijacked and captured. Compromised nodes are a serious threat and are also difficult to detect after attacks.
220.127.116.11 The lack of central servers and user administration:
It is one of most serious security issues in a zero configuration setting. Where there is no user intervention or centralized management, key generation, distribution and maintenance become very complicated. So, providing security services such as access control, data integrity and authentication of nodes, which need cryptographic keys, is not easy.
Ubiquitous computing environments can constantly change in excess of time because of the movement of devices. Any security solution involving static configuration of a node is improper because of the dynamic topology of the network. To achieve high availability, a distributed architecture without dependence on central management entities is needed. 
CHAPTER 6: ISSUES IN UBIQUITOUS COMPUTING
6.1 Hardware Prototypes:
Latest hardware systems design for ubiquitous computing has been oriented to experimental platforms for applications of invisibility and systems. Latest chips have been less important than combinations of existing components that create experimental opportunities.
Ubiquitous computing (UC) technology to be deployed was the Live board [Elrod 1992], which is a Xerox product. Two important pieces of prototype hardware supporting our research at PARC are:
6.1.1 The Tab:
It is a tiny information doorway. It has a pressure sensitive screen on top of the display for user interaction. It uses touchpad and displays are standard commercial units.
6.1.2 The Pad:
It is really a family of notebook-sized devices. Our first pad, the ScratchPad, plugged into a Sun SBus card and provided an X-window-system-compatible writing and display surface. This same design was used in our first the live boards and wall-sized displays. Our later untethered pad devices, the MPad and XPad, continued the system design principles of X-compatibility, simplicity of flexibility, and construction in hardware and software expansion. 
6.2 Issues of hardware components:
The new system of tabs, pads, and boards, ub