Welcome to the World of Computing

A Paper Presentation on

WELCOME TO THE WORLD OF COMPUTING

 ABSTRACT  INTRODUCTION  DISTINCTION BETWEEN WIRELESS AND MOBILE.  MOBILE DEVICES.  CHALLENGES IN MOBILE COMPUTING.  MERITS.  DEMERITS.  APPLICATIONS.  CONCLUSION.  BIBILOGRAPHY.

 Mobile

Computing has been undergoing a bit of renaissance lately. A Few years ago it was a simple matter of finding a data compatible mobile phone, a PC card modem, and a matching cable and installing it as modem. then people started to use PDA’s as well. Cell phones started to come with infrared ports to allow communication with laptops. Then cell phones started to come with modems built in. The connecting methods of mobile computing, its introduction, connection types, factors affecting connections, mobile applications and its limitations are explained.

 Wireless networking technology has engendered a new era of computing, called mobile computing. mobile computing is an umbrella term used to describe technologies that enable people to access network services any please , any time , and any where. Ubiquitous computing and nomadic computing are synonymous with mobile computing. mobile computing helps user’s to be productive immediately by reducing the training requirements associated with traditional automated data collection methods and provides a higher Level of portability than keyboard based systems field based uses can access any information available from the system at any time to make critical business decisions this information is available at the point of use wherever and whenever they need it.  Portable devices like laptop and palmtop computers give mobile users access to diverse sources of global information any where and at any time.  One of the most important and highly publicized recent developments in the PC world has been the introduction of the pen interface. by using stylus to replace the keyboard , mobile computers are turning thousands of computer illiterate people especially those  Involved with field based data collection into computer users. the market potential and breadth of application requirements for mobile computing has Prompted Numerous hardware and Software Companies to focus their efforts in providing solutions to the vertical form oriented market place .  The pen interface allows users to interact with the computer in a very natural familiar way by entering text, numbers and graphics in “electronic ink “ directly on the screen the pen interface also provides users with highly intuitive and efficient applications, whether tapping graphical icons to navigate through applications or selecting of options from scrolling lists and check boxes .  Mobile computing applications can closely simulate the original paper one form line providing users with a familiar look and feel through the use of the latest PCMCIA technology data storage is large, fast and more efficient with minimal power consumption and the highest level of ruggedness. While communications via modem Or wireless is also tightly integrated, fulfilling the requirements of the mobile user and standardized ports give users across to printers, barcode readers and various other peripheral devices.

o DISTINCTION BETWEEN “WIRELESS” AND “MOBILE

 Wireless refers to the method of transferring information between computing devices, such as a personal data assistant (PDA), and a data source, such as an agency data base server, with out a physical connection. Not all wireless communication technologies are mobile. For example, lasers are used in wireless data transfer between buildings, but can’t be used in mobile communications at this time.  Mobile simply describes a computing device that is not restricted to a desktop. A mobile device may be a PDA. A smart cell phone or web phone a laptop computer or any one of the numerous other devices that allow the user to complete computing tasks without being tethered, or connected, to a network. Mobile computing does not necessarily required wireless communication .in fact it may not require communication between devices at all.

Here we have seven different types of mobile devices  Laptop computers.  PDA’s and, handheld PC’s.  Pagers.  Smart phones and cellular phones.  Task devices, such as bar code readers.  Bluetooth.  Bridge.

 Laptops are typically used and supported in the same way as desktop PC’s. in fact many organizations have replaced desktops with their portable cousins , as the work force has grown increasingly mobile.

 PDA’s however, Are the least planned for and supported devices. they are undergoing rapid evolution and are being brought into organizations in the same way the earliest PC’s were .that is adventurous early adopters buy the devices for their personal use and then ask IT departments to integrate the devices in to the corporate IT environment. at present PDA’s are most often used for storing and synchronizing personal information such as addresses, schedules and E-mail .however the medical industry has developed numerous applications for PDA’s .at least one web ring( a collection of websites with a common topic) has been created to discuss medical software that automates functions such as patient and diagnostic data entry ,patient monitoring and diagnosis ,and messaging .in a hospital setting, these applications may include wireless communication between staff members handheld devices and a base station at which patient information is stored .  Smart phones that allow users to access phone calls, two way radio transmissions, paging and data transmissions on one device are also finding applications in hospitals and other situations that have intense and constant need for time sensitive communications.  Pagers that support one and two way text messaging are also used in similar situations .third party vendors most often provide support for these devices .  Task devices such as the parcel tracking devices used by FEDERAL EXPRESS(Fed ex) and the UNITED PARCEL SERVICE (ups) delivery personal are most often bought as part of a complete system from a third party vendor. Because they are frequently mission critical most corporations support task devices as rigorously as desktop computers.  Bluetooth, a short range wireless standard that specifies radio connections between devices within a ten meter range of each other. Bluetooth is designed as a personal area network (PAN or WPAN for “ wireless personal area network”)technology with a wide variety of theoretical uses .

  Bridge, a device that connects two local area networks (LAN’s), or two segments of the same LAN. bridges simply forward packets from one segment to another without analyzing or routing messages .

this allows them to connect dissimilar networks (ex :a bridge can connect an Ethernet and Token ring network).

 Wireless and mobile environments bring different challenges to users and service  Providers when compared to fixed ,wired networks .physical constraints become much more important, such as device weight, battery power, screen size, portability, quality of radio transmission, error rates . mobility brings additional uncertainties, as well as opportunities to provide new services and supplementary information to users in the locations where they find themselves. the major challenges in mobile computing are described including ;bandwidth, high error rate, power restrictions ,security ,limited capabilities, disconnection and problems due to client mobility.

 Wireless networks deliver lower bandwidth than wired networks. as a result, mobile applications have to be carefully designed to control the bandwidth consumption.  Software techniques to improve effective bandwidth usage include data compression logging requests to combine multiple short ones , lazy write back, difference based updates, caching , pre fetching, usage of proxy, priority scheduling etc.

 The network quality varies as the mobile computer moves across the heterogeneous network connections . the wireless environment exhibits higher error rates, which results in retransmission and affects the quality of service . by minimizing the usage of wireless transmission , the data is less exposed to transmission errors. in addition ,error correction schemes can be employed to improve performance . however , these schemes add to the communication overhead and reduce the usable band width.

 Mobile computers are concerned with the limited power supply, an issue that does not appear in distributed wired environment. Hardware improvements on batteries can help to lengthen the life of a charge and reduce the battery weight. In addition effective software operations can help to lower the power consumption. examples include: shifting the processing to a fixed host, aggressively caching and pre fetching data to reduce disk traffic, and transmitting less data while receiving more.  Security and piracy are of specific concerns in wireless communication because of the ease of connecting to the wireless link anonymously. Common problems are impersonation , denial of service and tapping. The main technique used in encryption . in personal profiles of users are used to restrict access to the mobile units.

 Unlike stationary computers mobile computers are similar in physical size and have smaller storage capacity. PDA’s like info pad and parc tab are designed to have extreme portability and provide ubiquitous information access. However, their application relies heavily on the interoperability of the pads and other servers. even ordinary laptops typically have less RAM and smaller hard disks than stationary computers.

 Disconnection and be voluntary or involuntary. Voluntary disconnection occurs when mobile users want to disconnect the mobile unit from the network temporarily, like working on a plane. Involuntary disconnection is mainly due to network failures.  The mobile application should not be disrupted under these circumstances. some applications are designed to run entirely locally on the mobile unit, but it may not be feasible for distributed applications where users have to communicate with one another. Again, pre fetching and lazy write-back are some useful techniques that allow to work under disconnection.  The CMU CODA file system allows shared files to be modified even during disconnections.  Upon reconnection, application-specific conflict resolution schemes are used in the file servers to reconfile any update conflicts maybe by various clients. it also uses concurrency control and pre fetching techniques .however ,this approach is designed mainly for file systems and does not for all kinds of applications .

 There are two types of mobility described(a)mobility of clients and(b)mobility of resources .mobility of clients raises the issues of unique naming of the clients and finding their current locations. unlike stationary computers ,where information on location is configured statically mobile computers have to configure information dynamically mobility of resources addresses this problem. When a mobile host moves into a new cell or administrative domain , it has to discover the resources available there . at the same time , any server that needs to communicate with the mobile host has to identify its new location. Location transparency should be provided to the mobile applications by the underlying runtime system so that the users are not aware of the effects of mobility.

The benefits of automating data collection applications with mobile computing are the reduction of hard and soft costs, enhancement of revenue potential , and a distinct competitive advantage through:  Improving the data collection process.  Improving data accuracy.  Reducing paper work.  Facilitating collection of more useful information.  Eliminating redundant data entry.  Reducing administrative costs.  Reducing billing errors.  Reducing data backlog.  Improving information flow.  Allowing faster adaptation to change the business conditions.  Increasing responsiveness and customer satisfaction.  Providing access to unavailable information.  The demerits of the mobile computing are discussed as fallows.  Information access via a mobile device is plagued by low available band width, poor connection maintenance, poor and addressing problems. Unlike their wired counter parts, design of software for mobile devices must consider resource limitation, battery power and display size. Consequently, new hardware and software techniques must be developed. for example, application need to be highly optimized for space, in order to fit in the limited memory on the mobile devices.  Mobility brings additional uncertainties , as well as opportunities to provide new services and supplementary information to users in the location where they find themselves. in general, most application software, operating systems, and network infrastructures are intended for more conventional environments , and so the mobile, wireless user has great difficulty exploiting the computational infrastructure as fully as he or she might . there is an emerging consensus among researchers that a new architecture and dynamic infrastructure is an appropriate way to address this problem .  Day by day as the standard of the mobile computing is increasing the boons of mobile computing are changing to banes. eg : the most deadly terrorist attack occurred on September 11th , 2001  New technical and application developments have established that mobile systems can be a cost effective, efficient and productive solution in several different types of application environments . they are :-a new generation of satellites , especially low earth orbit systems (LEOS)are under development with the internet in mind .companies like Teledesic and Orbcomm are actively promoting internet access .  Vertical industries where mobile technology has already been successfully adopted include consumer goods. Delivery and root sales , government , healthcare , market research , pharmaceuticals , transportation and utilities .

Typical applications include inventory, merchandising , order entry and sales automation. features found in these applications usually provide access to stock and pricing information, monitor promotion , and perform shelf space analysis including number of facings and product age . customer detail helps reps to act more as consultants than order takers .

 With fierce competition and an increasing inventory , having timely and accurate information is more important than ever.

 Applications center around assessments, inspections, and work orders. Most of these applications involve auditing some sort of facility or process(food service, restaurant, nursing home, child care, schools, commercials and residential buildings).

 The focus in this industry has been on automating patient records, medication, dispension, and sample collection. A common goal is to leverage mobile computing in the implementation of positive patient identification.

 Automating the survey the process has enabled these companies to get their data more accurately and quickly while being able to customize their queries at will.  In addition to the reps need to perform account management and cell reporting functions ,the FDA’s requirements for physician signatures for all drug samples dispensed was an ordered complication that was eliminated through the use of mobile technology.

 Transforming freight damage inspection from paper to mobile computing greatly expedites the process and reduces cost by providing online pre-shipment inspections. This technology also offers a more efficient means of storing and transmitting maintenance inspection reports . in conjunction with GPS(global positioning systems),  Mobile computing allows companies to provide better customer service by being continuously aware of exactly where any given shipment is when in transit .

 Eliminating the rekeying of data and providing a means to perform on site analysis are instrumental to an industry that is required to perform inspection on routine basis.

 There’s more happening than many people suspect. the difficulty , though is to provide the right network , the right device , the right price and the right applications. Wireless is not wired, and there are numerous advantages and disadvantages. The wireless industry “mindset” is different from the computer communities. these different philosophies produce what we call a “wireless-web culture clash”. Also much of the information we obtain via the internet isn’t worth paying for in a mobile environment. the internet will change is already changing the way mobile companies and computer companies offer products and services, and deal with customers. Indeed, many wireless subscribers will demand these changes, ranging from online customer service to electronic bill paying to creating profiles that automatically transmit personalized information via the internet to wireless devices. We are in a period of tremendous change. It’s mobile computing jungle where old technologies must evolve to survive and where proponents of new technologies are jockeying for dominance. it’s a dangerous and exciting time where existing business models can crumble and more nimble , innovative companies can usurp established institutions.  Uncovering these developments, analyzing there impact and recommending solutions to corporations is what wireless internet and mobile computing consulting is all about.  Mobile computing is rapidly becoming popular, and user demand for useful wireless applications is increasing.  Additionally, this paper shows how these behavioral extensions serve as a powerful abstraction for practical systems.  In this paper, we have looked at issues related to portable devices, merits, demerits and applications in mobile environment.  Because of these banes of mobile computing the security level should be improved.

 Terry Watson:- application design for wireless computing. . Application design for wireless computing; M –mail a case study of dynamic application portioning in mobile computing.

Christine julien and gruia – catalin roman : active co- ordination in adhoc networks.

 Raymond j.Brunsting:- quality of service issues in wireless networks.