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1 Volume 3, Issue 9, September 2013 ISSN: X International Journal of Advanced Research in Computer Science and Software Engineering Research Paper Available online at: Mobile Computing Devashish Goswami Asst Prof, Department of Computer Application HKBK Degree College, Bangalore, India. Abstract: Mobile computing is becoming increasingly important due to the rise in the number of portable computers and the desire to have continuous network connectivity to the Internet irrespective of the physical location of the node. Mobile computing offers significant benefits for organizations that choose to integrate the technology into their fixed organizational information system. Ranging from wireless laptops to cellular phones and Wi-Fi/Bluetooth enabled PDA s to wireless sensor networks, mobile computing has become ubiquitous in its impact on our daily lives. Mobile computing is a versatile and potentially strategic technology that improves information quality and accessibility, increases operational efficiency, and enhances management effectiveness. The goal of this paper is to point out some of the limitations, characteristics, applications and issues of mobile computing. Keywords: Mobile Computing, Wireless Technology, Application, Issues, Limitation, I. Introduction What is mobile computing? Mobile computing is human computer interaction by which a computer is expected to be transported during normal usage. Mobile computing involves mobile communication, mobile hardware, and mobile software. Mobile computing is the ability to use computing capability without a pre-defined location and connection to a network to publish and subscribe to information. Mobile computing as a generic term describing ability to use the technology to wirelessly connect to and use centrally located information and application software through the application of small, portable, and wireless computing and communication devices. The term "Mobile computing" is used to describe the use of computing devices, which usually interact in some fashion with a central information system--while away from the normal, fixed workplace. Mobile computing technology enables the mobile worker to create, access, process, store and communicate information without being constrained to a single location. By extending the reach of an organization's fixed information system, mobile computing enables interaction with organizational personnel that were previously disconnected. Mobile computing is the discipline for creating an information management platform, which is free from spatial and temporal constraints. The freedom from these constraints allows its users to access and process desired information from anywhere in the space. The state of the user, static or mobile, does not affect the information management capability of the mobile platform being constrained to a single location. To facilitate the data management activities, users can carry Personal Digital Assistant (PDA), laptop, cell phones, etc. At present the current technology only provides limited transaction processing capabilities but soon such facilities will be available on all mobile devices such as cell phones, laptops, palmtops, etc. This discipline allows us to define a connectivity mode, which we refer to as "Mobile Connectivity". We define mobile connectivity mode as: Mobile connectivity: The mobile connectivity between two nodes exists if they are continuously connected through wireless channel, and can utilize the channel without being subjected to spatial and temporal constraints. II. Characteristics Of Mobile Computing Mobile computing is accomplished using a combination of computer hardware, system and applications software and some form of communications medium. Powerful mobile solutions have recently become possible because of the availability of an extremely powerful and small computing devices, specialized software and improved telecommunication. Some of the characteristics of mobile computing are based on following: 1. Hardware: The characteristics of mobile computing hardware are defined by the size and form factor, weight, microprocessor, primary storage, secondary storage, screen size and type, means of input, means of output, battery life, communications capabilities, expandability and durability of the device. 2. Software: Mobile computers make use of a wide variety of system and application software. The most common system software and operating environments used on mobile computers includes MSDOS, Windows 3.1/3.11/95/98/NT, UNIX, android etc. These operating environments range in capabilities from a minimalist graphically- enhanced- penenabled DOS environment to the powerful capabilities of Windows NT. Each operating system/environment has some form of integrated development environment (IDE) for application development. Most of the operating environments provide more than one development environment option for custom application development. 3. Communication: The ability of a mobile computer to communicate in some fashion with a fixed information system is a defining characteristic of mobile computing. The type and availability of communication medium significantly 2013, IJARCSSE All Rights Reserved Page 846

2 impacts the type of mobile computing application that can be created. The way a mobile computing device communicates with a fixed information system can be categorized as: (a) connected (b) weakly connected (c) batch and (d) disconnected. The connected category implies a continuously available high-speed connection. The ability to communicate continuously, but at slow speeds, allows mobile computers to be weakly connected to the fixed information system. A batch connection means that the mobile computer is not continuously available for communication with the fixed information system. In the batch mode, communication is established randomly or periodically to exchange and update information between the mobile computer and fixed information systems. Mobile computers may operate in batch mode over communication mediums that are capable of continuous operation, reducing the wireless airtime and associated fees. Disconnected mobile computers allow users to improve efficiency by making calculations, storing contact information, keeping a schedule, and other non- communications oriented tasks. This mode of operation is of little interest because the mobile device is incapable of electronically interacting and exchanging information with the fixed organizational information system. Exchange of information with a disconnected mobile computing device can only be accomplished by manually entering information into the device or copying from the device's screen and manually entering the information into the fixed information system. This mode of information exchange is no more efficient than using paper and is effectively nonexistent, since virtually all modern mobile computing hardware is capable of some form of native electronic data communications. Data Communications is the exchange of data using existing communication networks. The term data covers a wide range of applications including File Transfer, interconnection between Wide-Area-Networks (WAN), facsimile (fax), electronic mail, access to the internet and the World Wide Web (WWW). Available Technology There are many communications technologies available today that enable mobile computers to communicate. The most common of these technologies are: (a) Wireless Local Area Networks (WLANs) (b) Satellite (c) Cellular Digital Packet Data (CDPD) (d) Personal Communications Systems (PCS) (e) Global System for Mobile communications (GSM) (f) RAM and ARDIS data networks (g) Specialized Mobile Radio (SMR) service (h) one and two-way paging (i) plain old telephone system (POTS) (j) Internet (k) infra-red (l) docking (serial, parallel, LAN) and (m) disk swapping. These diverse communications technologies make available a continuum of connectivity that provides communications capabilities ranging from manual-assisted batch transfers to high-speed continuous communication. III. How Mobile Computing Work In mobile computing platform information between processing units flows through wireless channels. The processing units (client in client/server paradigm) are free from temporal and spatial constraints. That is, a processing unit (client) is free to move about in the space while being connected to the server. This temporal and spatial freedom provides a powerful facility allowing users to reach the data site (site where the desired data is stored) and the processing site (the geographical location where a processing must be performed) from anywhere. This capability allows organizations to set their offices at any location. The discipline of mobile computing has its origin in Personal Communications Services (PCS). PCS refers to a wide variety of wireless access and personal mobility services provided through a small terminal (e.g., cell phone), with the goal of enabling communications at any time, at any place, and in any form. These PCS are connected to Public Switched Telephone Network (PSTN) to provide access to wired telephones.pcs include high-tier digital cellular systems for widespread vehicular and pedestrian services and low-tier telecommunication system standards for residential, business, and public cordless access applications. High-tier digital cellular systems include Global System for Mobile Communications (GSM) IS-136 TDMA based Digital Advanced Mobile Phone Services (DAMPS) Personal Digital Cellular (PDC) IS-95 CDMA-based cdmaone System Low-tier telecommunication systems include Cordless Telephone 2 (CT2) Digital Enhanced Cordless Telephone (DECT) Personal Access Communication Systems (PACS) Personal Handy Phone Systems (PHS) Several wideband wireless systems and special data systems have been developed to accommodate internet and multimedia services. Mobile computing is not one technology. It is a range of solutions that enable user mobility by providing access to data anytime, from anywhere. Handheld Mobile Computing Device Wireless Connection Data Communication Technology Component Figure: Mobile Computing Components Wired Connection Information System Component 2013, IJARCSSE All Rights Reserved Page 847

3 As shown in figure, mobile computing has three components 1. Handheld, mobile computing device. 2. Connecting technology that allows information to pass back and forth between the sites s centralized information system and the handheld device and back. 3. Centralized information system Here is how mobile computing works 1. The user enters or access data using the application on handheld computing device. 2. Using one of several connecting technologies, the new data are transmitted from handheld to site s information system where files are updated and the new data are accessible to other system user. 3. Now both systems (handheld and site s computer) have the same information and are in sync. 4. The process work the same way starting from the other direction. The process is similar to the way a worker s desktop PC access the organization s applications, except that user s device is not physically connected to the organization s system. The communication between the user device and site s information systems uses different methods for transferring and synchronizing data, some involving the use of radio frequency (RF) technology. In today s market, the three most commonly used wireless data transfer methods are: 1. Wireless local area network (Wireless LAN) 2. Wireless Internet or wireless Web. 3. Data syncing or hot syncing. This is not a wireless data transfer method, although it is often reference as wireless. Data syncing used docking cradles or docking stations that are connected to a LAN to transfer data from the device to the organization s information system. 1. Wireless LAN Wireless LAN is a flexible data and communication system used in addition to, or instead of, a wired LAN. Using radio frequency (RF) technology, wireless LANs transmit and receive data over air, minimizing the need for wired connection and enable user mobility. Unlike such technologies such as infrared, wireless LAN is not a line of sight technology. Therefore the handheld device can operate anywhere within the coverage area. In a wireless LAN user enters data into a handheld device such as personal digital assistant (PDA), laptop or tablet that has a special wireless LAN card. This card has an antenna that transmits the data in real time using radio frequency technology to an access terminal, usually connected to a ceiling or wall. The access terminal is connected to the local area network and sends the data- received or request for data- from the handheld to site s information system. Conversely, data from site s information system can be sending to the handheld using same technology. Figure: Wireless LAN 2. Wireless Internet Wireless Internet, also known as the wireless web, provides mobile computing access to data using the Internet and specially equipped handheld device. Using a web phone or a latest PDA phone with micro web browser, the user can display data accessible from the internet. The mobile device connected to the cellular system sends the request to computer link server. This server act as a gateway that translates signal from the handheld device into language the web can understand, using an access and communication protocol. One of the leading protocols is WAP (Wireless application protocol). The server also forwards the request over the internet to a web site, such as Yahoo, Google or the organization s site information system. The web site response to the request and forwards the information back through the link server. Again the response is translated into a Wireless Markup Language (WML) so it is viewable on the small 2013, IJARCSSE All Rights Reserved Page 848

4 cell phone screen. This translated response is then sent to the cellular system and finally to the Web-enable mobile computing device. Example for the current uses of wireless internet include accessing short s, quick look up capabilities (stocks, weather, flights, movies, restaurants, retail transaction, alert messaging etc. Figure: Wireless Interne 3. Data Synchronization Data Synchronization provides many of the benefits of mobile computing without the cost of installing wireless LAN equipment or needing access to the Internet. Information is periodically downloaded from the organization s information system to the handheld device and then uploads from the device to organization s information system. Updating of information is available in both the sides. The major drawback of data synchronization is that it does not provide real time access to data. Data syncing is not a wireless data transfer method because data are transferred from the mobile computing device to the site s information system through a docking (or syncing) cradle wired to the LAN. It is commonly grouped under the general term of wireless because the user s device is physically attached to the LAN only during the batch data transfers. Data Synchronization solutions have been used widely in health care and are typically the first use of wireless because of the low cost to implement and the wide range of application that deliver real value to the organization. Generally, data syncing solutions work best in health care settings where 1. Mobile user has access to the LAN for periodic data updates and 2. The work being performed does not require access to the most current information. Figure: Data Synchronization Mobile Computing Devices Some of the mobile computing devices have already been mentioned in order to describe the different wireless data transfer options. Following is a closer look at the range of products and functions. Although there are many products on the market, handheld devices fall into several categories, each with specific capabilities and options. Device Type Product Features Web Phone : Internet browser functions Cellular phone with Internet access Limited , calendar, appointment PDA Phone : Combination of web phone with PDA personality scheduling and directories. Internet browser functions. , calendar, appointment scheduling 2013, IJARCSSE All Rights Reserved Page 849

5 and directories. Personal Digital Assistant(PDA) or Pocket PC , calendar, appointment scheduling, and Handheld computerized information organizer; directories. examples include Palm Pilot, Handspring Visor, Some desktop application functions. E.g., Word Compaq ipaq and excel. Pen-based system for data entry Handheld PC : Small hand size personal computer with a keyboard Tablet/Laptop Tablet is a flat paneled. Laptop is also known as PC notebook Bar coding. More powerful than a PDA device. Some desktop application functions. E.g., Word and excel. Keyboard for data entry. Voice reorganization and recording option Bar coding All desktop functionality Tablets use pen or touch screen technology Current Technology Issues and Limitation Although wireless technology is maturing rapidly, several limitations stand in the way of widespread adoption. Good decision about technology need to be based on a realistic understanding of current performance and how limitations can be addressed Technology Mobile Computing Devices Current Issue and Limitation Handheld device such as PDAs and pocket PCs have small screens, short battery life, limited processing power, and rudimentary data integration capability. Wireless LANs Wireless Internet Data Synchronization Laptop and tablets provide greater processing, battery life, and data viewing power, but are considerably larger heavier, with limited data interfacing capabilities. Data transfer speed is currently slower than traditional LANs. Real Time interfaces between mobile computing and LANbased applications are custom developed for each site and therefore expensive to create and maintain. Wireless Internet technology faces similar issues with data transfer speed. Additional problem of multiple connectivity standards. Same device limitations as described above plus the need for application specific cradles wired throughout the service area. Supports only batch data updates. Mobile computing device capabilities With mobile computing devices, the selection decisions are limited. In many cases, the vendor will have already made the device decision, with only a small range of customer-specific options. However, it is important for new users to understand what they are getting in terms of current and add-on capabilities. Two considerations are: 1. Expandability: Most users do not want to carry several devices; i.e., one for charge entry, one for ordering, and one for notes. Can the handheld device support today s application needs as well as plans for the future? Special features like having a color display or voice recognition capabilities may be very important for some caregivers but not others, depending on what they must use the device to accomplish. What are the special functions needed for the handheld to support the application and enhance ease of use? Is it available now? What are expected changes for next year? Key questions to consider are: What device(s) and operating system(s) does the application use? What is the screen resolution of the device? What are the general specifications for battery life, weight, processing power? What is the capability of the handheld applications itself? What is the future direction for development? 2. Integration with existing systems: The integration of a new application with the existing systems is always a challenge. Besides identifying the data, it is necessary to consider data formatting, coded data value, update capabilities, ownership, and access rights for all users in the process. Careful examination of the workflow, end- 2013, IJARCSSE All Rights Reserved Page 850

6 user data needs, and functionality of the systems will require technical resources (both vendor and IS) and process experts (both vendor and end user) to create a workable, effective solution. Key questions to consider are: 1. Will the application integrate with legacy systems? 2. What data needs to be received, updated, and sent? 3. How does the system distribute and synchronize files? 4. How is data ownership established? 5. What methods are used to maintain data security? IV. Mobile Computing Applications And Benefits The real power of mobile computing becomes apparent when mobile hardware, Software, and communications are optimally configured and used to accomplish a Specified mobile task. Although many varied applications exist, mobile computing applications can generally be divided into two categories--horizontal and vertical. 1. Horizontal: Horizontal applications have broad-based appeal and include software that performs functions such as: (a) ; (b) Web browsing; (c) word processing; (d) scheduling; (e) contact management; (f) to-do lists; (g) messaging; (h) presentation. These types of applications usually come standard on Palmtops, Clamshells, and laptops with systems software such as Windows Vertical: Vertical applications are industry-specific and only have appeal within the specific Industry for which the application was written. Vertical applications are commonly used in industries such as: (a) retailing; (b) utilities; (c) warehousing; (d) shipping; (e) Medical and (f) law enforcement and public safety. These vertical applications are often transaction oriented and normally interface with a corporate database. Other application areas include: (a) mining; (b) forestry; (c) agriculture; and (d) surveying etc. Benefits of mobile computing Mobile computing technology offers a quick and easy way to increase efficiency, productivity and profitability while gaining better control of our operations. The power and data storage capacity of today s handheld PCs and Personal Digital Assistants (PDAs) has made low-cost mobile computing a practical reality. Today s world mobile computing is using in various fields. 1. Improved Information Accessibility: Mobile computing enables improvements in information accessibility. The degree of improvement is directly dependent upon the mobile hardware and communications equipment in use. Mobile computing technology (hardware, software, and communications) provides a wide range of options that can be mixed and matched to fit the needs of each individual mobile computing application. The improvements in information accessibility enabled by mobile computing result in improved information flow both to and from the central fixed information system. The mobile computer enables quick and efficient information retrieval from the central information system. The ability to access central information and make fixed or ad hoc queries of corporate databases enables employees to get the information they need to complete the job. The mobile computer also enables transmission of current operational data, in native digital format, from the mobile user to the central fixed information system. Once transmitted to the fixed information system, the data from the mobile user can be processed and made available for all other users of the central information system. Thus, the information available to a mobile user from the central information system reflects current information from other mobile users as well. Mobile computing eliminates the delay that occurs when an employee must physically return to the office at the end of the day and submit paper forms so that data entry personnel can enter the information into the central information system. Even employees that are not continuously connected to the fixed organizational information system via a wireless link will experience significantly improved information accessibility through mobile computing. One phone call at the end of the day from the mobile user via a standard modem is all that is required to transmit the entire day's transactions to the central computer, saving travel and data entry time. Additionally, any scheduling or assignment changes for the mobile employee for the following day can be transmitted to the employee during the same phone call. Mobile computing also significantly speeds information accessibility when other media, such as: (a) facsimile; (b) audio files; or (c) still images are concerned. Digital images or audio files can be accessed by the mobile user or transmitted from the mobile user to the central fixed organizational information system. If matched properly to the work environment and task to be accomplished, the mobile computer will always be in the possession of the mobile worker during the course of the day. Especially in the connected or weakly connected modes of operation, this means that the mobile employee may be contacted throughout the workday via the mobile computing device. Additionally, it means that the employee has access to other mobile employees via or other messaging schemes. As with many mobile computing applications, the type of mobile application and the hardware, software, and communications used to support it will normally determine the degree and type of information accessibility. The direct measurable results of improved information accessibility-both to and from the mobile worker are many. They include: (a) improved customer service; (b) reduced cycle times; (c) greater accuracy; (d) fewer complaints; and (e) a reduction in required intermediate support staff. 2. Increased Operational Efficiency: Mobile computing enables improvements in the operational efficiency of organizations that integrate the technology into their fixed information systems. It enables the computing power and information contained within the fixed information system to be structured around the optimum work flow of a mobile worker, instead of altering the mobile worker's work flow to meet the optimum configuration for 2013, IJARCSSE All Rights Reserved Page 851

7 computing. The mobile computer stays with the mobile employee, instead of the employee being required to travel to the computer. Mobile computing can improve efficiency in many ways, including: (a) saving time; (b) reducing waste; (c) cutting cycle times; (d) reducing rework; (e) enabling business process reengineering; (f) improving accuracy; (g) decreasing time spent on customer complaints; and (h) reducing unnecessary travel. 3. Increased Management Effectiveness: Mobile computing technology can improve management effectiveness by improving information quality, information flow, and ability to control a mobile workforce. It makes the most current and accurate information available to both the mobile worker and the users of the fixed information system with which the mobile worker communicates. These benefits can be seen in all areas of the information System, often, it is the improved ability to manage operations that is partly responsible for the performance improvements seen in companies that introduce mobile computing technology. 4. For Estate Agents: Estate agents can work either at home or out in the field. With mobile computers they can be more productive. They can obtain current real estate information by accessing multiple listing services, which they can do from home, office or car when out with clients. They can provide clients with immediate feedback regarding specific homes or neighborhoods, and with faster loan approvals, since applications can be submitted on the spot. Therefore, mobile computers allow them to devote more time to clients. 5. Emergency Services: Ability to receive information on the move is vital where the emergency services are involved. Information regarding the address, type and other details of an incident can be dispatched quickly, via a Cellular Digital Packet Data (CDPD) system using mobile computers, to one or several appropriate mobile units, which are in the vicinity of the incident. 6. In courts: Defense counsels can take mobile computers in court. When the opposing counsel references a case which they are not familiar, they can use the computer to get direct, real-time access to on-line legal database services, where they can gather information on the case and related precedents. Therefore mobile computers allow immediate access to a wealth of information, making people better informed and prepared. 7. In companies: Managers can use mobile computers in, say, and critical presentations to major customers. They can access the latest market share information. At a small recess, they can revise the presentation to take advantage of this information. They can communicate with the office about possible new offers and call meetings for discussing responds to the new proposals. Therefore, mobile computers can leverage competitive advantages. 8. Credit Card Verification: At Point of Sale (POS) terminals in shops and supermarkets, when customers use credit cards for transactions, the intercommunication is required between the bank central computer and the POS terminal, in order to effect verification of the card usage, can take place quickly and securely over cellular channels using a mobile computer unit. This can speed up the transaction process and relieve congestion at the POS terminals. 9. Field Sales: The operational efficiency of sales personnel is significantly enhanced through mobile computing. An excellent example of these improvements can be seen by examining how mobile computing improves the efficiency of remote insurance and financial planning sales. The mobile computer frees the sales agent to meet with the client at the client's home, office, or other location. Customer data is collected, estimates and comparisons are immediately calculated, the customer decides on the program of choice, the central computer is immediately updated, and the customer is enrolled in the insurance or financial planning program. Without mobile computing, this sales process would take days instead of minutes. In addition to accessing and updating customer account information, mobile sales personnel can accomplish tasks such as printing invoices or other information to leave with the customer. 10. Transportation and Shipping: Using mobile computers in conjunction with GPS/GIS and an accompanying vehicle information system (VIS), the operations of an entire transportation fleet can be managed from a central location. The central office knows the location, status, and condition of all vehicles, and operators have two-way communication with the operations center. Using this information, vehicles can be optimally dispatched to maximize efficiency as measured by: (a) time; (b) fuel consumption; and (c) delivery priority. The mobile computers enable significant performance improvements, achieved simultaneously with operational cost reductions. 11. General Dispatching: Mobile computers used in conjunction with Global Positioning System (GPS) and Geographical Information System (GIS) data allow significant improvements in the operational efficiency of various dispatch operations. For example, the central computer at a taxi company can track the location and status of all its taxicabs and electronically dispatch the most appropriate car to a customer's location. Additionally, the central computer can calculate an accurate approximation of when the taxi will arrive, enabling improved customer service. 12. Hotel Operations: Connecting the cleaning and hospitality staff of a hotel with mobile computing can significantly improve the efficiency of hotel operations. As guests check out and rooms are vacated, the central computer wirelessly signals cleaning staff that the rooms are ready for cleaning. Problems that are identified during cleaning, such as broken appliances or faulty plumbing, are immediately communicated to the mobile maintenance team for action. As soon as cleaning is complete and repairs are accomplished, the cleaning staff member wirelessly updates the central computer and the room is immediately available for check-in by a new guest. The same system can be used to efficiently direct mobile hospitality personnel in response to guest requests for information and service. 2013, IJARCSSE All Rights Reserved Page 852

8 13. News Reporting: Mobile computers dramatically improve the efficiency of news media operations. Reporters equipped with mobile computers and accompanying electronic devices can cover news or sporting event, take digital video or still photographs, digitally record audio interviews, compose the text of the news story, and transmit the completed product back to the central agency for editing and immediate publication. In the media industry, the timing and quality of news coverage is critical. Mobile computing increases the quality of the information from the media crews and significantly decreases the time required to process and transmits the story for publication. 14. Health Care: Mobile medical care, whether in-home, on the road, or within a hospital, is more efficient with mobile computing. The mobile healthcare worker can access patient records for reference purposes, and is able to update records with current diagnosis and treatment information. Emergency medical technicians (EMTs) responding at the scene of an accident can use mobile computers to capture patient information, treatments accomplished vital signs, and other critical data. This information is wirelessly transmitted to the receiving hospital, which then prepares to receive and treat the patient, or recommend another hospital facility with more appropriate treatment facilities depending upon the nature and severity of the injuries. The more efficient handoff between ambulance EMTs and hospital staff made possible by mobile computing can save lives that otherwise might have been lost. 15. Fieldwork: Almost any form of fieldwork can be made significantly more efficient through the application of mobile computing. Parking control officers and utility inspectors are two examples of field workers who can receive operational benefits from mobile computing. Parking control officers use handheld computers to check the registration and violation history of parking offenders. Parking violations are issued immediately and towing/backup can be requested when required. Utility inspectors have historically used paper forms to capture information such as consumer power consumption and utility equipment status (transformers, transmission towers, etc.). Using mobile computers, inspectors can be given instructions on inspections to be accomplished and information can be captured and validated at the source. 16. Mobile Automation: General business travelers also reap the benefits of mobile computing. , Spreadsheets, presentations, and word processing are the four primary tasks accomplished by these business travelers. Laptops, Palmtops, and portable Clamshell computers with usable-size keyboards enable businesspeople to stay in touch and accomplish the tasks they need for job effectiveness. Using powerful mobile computers in conjunction with high-speed connectivity, mobile workers can perform work normally accomplished at the office while on the road or in the field. 17. Results: Just as mobile computing enables improved operational efficiency, it also enables improved management effectiveness. Mobile computers make more timely and accurate information available to managers. Mobile computers improve the manager's ability to track work in progress. They also improve the ability of managers to communicate with mobile personnel. Additionally, mobile computers provide better information to mobile employees, so they can make more informed decisions locally and minimize the need for management decisions from the central office V. LIMITATIONS OF MOBILE COMPUTING 1. Insufficient Bandwidth: Mobile Internet access is generally slower than direct cable connections, using technologies such as GPRS and EDGE, and more recently 3G networks. These networks are usually available within range of commercial cell phone towers. Higher speed wireless LANs are inexpensive but have very limited range. 2. Security Standards: When working mobile, one is dependent on public networks, requiring careful use of Virtual Private Network (VPN). Security is a major concern while concerning the mobile computing standards on the fleet. One can easily attack the VPN through a huge number of networks interconnected through the line. 3. Power consumption: When a power outlet or portable generator is not available, mobile computers must rely entirely on battery power. Combined with the compact size of many mobile devices, this often means unusually expensive batteries must be used to obtain the necessary battery life. Mobile computing should also look into Greener IT, in such a way that it saves the power or increases the battery life. 4. Transmission interferences: Weather, terrain, and the range from the nearest signal point can all interfere with signal reception. Reception in tunnels, some buildings, and rural areas is often poor. 5. Potential health hazards: People who use mobile devices while driving are often distracted from driving are thus assumed more likely to be involved in traffic accidents. Cell phones may interfere with sensitive medical devices. There are allegations that cell phone signals may cause health problems. 6. Human interface with device: Screens and keyboards tend to be small, which may make them hard to use. Alternate input methods such as speech or handwriting recognition require training. VI. Issues in Mobile Computing 1. Security Issues A. Confidentiality: Preventing unauthorized users from gaining access to critical information of any particular user. B. Integrity: Ensures unauthorized modification, destruction or creation of information cannot take place. 2013, IJARCSSE All Rights Reserved Page 853

9 C. Availability: Ensuring authorized users getting the access they require. D. Legitimate: Ensuring that only authorized users have access to services. E. Accountability: Ensuring that the users are held responsible for their security related activities by arranging the user and his/her activities are linked if and when necessary. F. Wireless networks have relatively more security requirements than wired network. A number of approaches have been suggested and also the use of encryption is has been proposed. 2. Bandwidth: Bandwidth utilization can be improved by logging (bulk operations against short requests) and compression of data before transmission. Additionally, lazy write back and file perfecting can help the network in times of peak demands. Lazy write back is very helpful in the sense that the data to be written may undergo further modifications. The technique of caching frequently accessed data items can play an important role in reducing contention in narrow bandwidth wireless networks. The cached data can help improve query response time. Since mobile clients often disconnect to conserve battery power the cached data can support disconnected operations 3. Location Intelligence: As the mobile computers move they encounter networks with different features. A mobile computer must be able to switch from infrared mode to radio mode as it moves from indoors to outdoors. Additionally it should be capable of switching from cellular mode of operation to satellite mode as the computer moves from urban and rural areas. In mobile computing as computers are working in cells and are being serviced by different network providers, the physical distance may not reflect the true network distance. A small movement may result in a much longer path if cell or network boundaries are crossed. It will also lead to updating of the location dependent information as described above. This can increase the network latency as well as risk of disconnection. Service connections must be dynamically transferred to the nearest server. However, when load balancing is a priority this may not be possible. 4. Power Consumption: Mobile Computers will rely on their batteries as the primary power source. Batteries should be ideally as light as possible but at the same time they should be capable of longer operation times. Power consumption should be minimized to increase battery life. Chips can be redesigned to operate at lower voltages. Power management can also help. Individual Components, be powered down when they are idle. 5. Revising the technical architecture: Mobile users are demanding. They are important to the business world. To provide complete connectivity among users the current communication technology must be revised to incorporate mobile connectivity. Additionally, application and data architectures must also be revised to support the demands put upon them by the mobile connectivity. 6. Reliability, coverage, capacity, and cost: At present wireless network is less reliable, have less geographic coverage and reduced bandwidth, are slower, and cost more than the wired-line network services. It is important to find ways to use this new resource more efficiently by designing innovative applications. 7. Integration with legacy mainframe and emerging client/server applications: Application development paradigms are changing. As a result of the IT industry's original focus on mainframes, a huge inventory of applications using communications interfaces that are basically incompatible with mobile connectivity have been accumulated. Still the application development trend is geared towards wired network. 8. End-to-end design and performance: Since mobile computing involves multiple networks (including wired) and multiple application server platforms, end-to-end technical compatibility, server capacity design, and network response time estimates are difficult to achieve. 9. Business challenges: In addition to these technical challenges, mobile computing also faces business challenges. This is due to the lack of trained professionals to bring the mobile technology to the general people and development of pilot projects for testing its capabilities. VII. Tactics for Success After the selection decision for a particular mobile computing application has been made, implementing the system just as carefully will help to ensure that the end users are satisfied and full value is realized. The following implementation tactics, based on the most recent mobile computing project experiences, should help projects move smoothly 1. Understand the integration of workflow, information flow, and technology: Mobile computing is not the entire solution; it addresses specific tasks within the care delivery process. Understanding the points where technology is provided and the information collected or displayed for the end user will lead to a clear map of the necessary changes in the current process and roles. In many projects, implementing the process, roles, and responsibility changes is far more challenging than installing the new technology. 2. Set user expectations: Take the time to under-stand, document, and set expectations related to each functionality and technology that will be installed. Many device manufacturers and application vendors claim incredible functionality and access to information. Remember that mobile does not necessarily mean wireless, real-time access to data. Make sure that end users are not led to believe that the application is going to give them access to the same services and functionality that they have on their PCs with wired connections. Mobile computing will give them basic functions with the added benefit of mobility 3. Pilot the application: A great implementation advantage with mobile computing is that piloting is possible. The cost for the handheld devices, software, and basic data synchronization interfacing is very low, especially if the vendor is willing to partner with the organization to gain experience with implementations and have reference sites. By starting small, users get a clear under-standing of how mobile computing impacts their work 2013, IJARCSSE All Rights Reserved Page 854

10 environment. Pilot implementations identify process and technology adjustments that will improve user acceptance and the overall success of the project when it is rolled out. VIII. Conclusion Mobile computing is an important, evolving technology. It enables mobile personnel to effectively communicate and interact with the fixed organizational information system while remaining unconstrained by physical location. Mobile computing offers significant benefits for organizations that choose to integrate the technology into their fixed organizational information system. Mobile computing is made possible by portable computer hardware, software, and communications systems that interact with a non-mobile organizational information system while away from the normal, fixed workplace. Mobile computing is a versatile and potentially strategic technology that improves information quality and accessibility, increases operational efficiency, and enhances management effectiveness. Mobile computing may be implemented using many combinations of hardware, software, and communications technologies. The technologies must be carefully selected and the applications designed to achieve the business needs required from the overall organizational information system. Here in this paper we have in term identified some of the challenging issues, applications of mobile computing along with few of the characteristics of Mobile computing. REFERENCES 1. Mobile Computing: Characteristics, Business Benefits, and the Mobile Framework, by James Bryan Zimmerman, University of Maryland European Division - Bowie State. 2. Challenging Issues and Limitations of Mobile Computing by Deepak G and Dr. Pradeep B S, Department of CSE, Dayananda Sagar College of Engineering, Department of CSE, Rajarajeswari College of Engineering, Bangalore, India 3. Wireless and Mobile Computing, by Fran Turisco and Joanna Case, First Consulting Group Mobile Computing, by Vijay Kumar, University of Missouri-Kansas City Kansas City, MO 64110, USA , IJARCSSE All Rights Reserved Page 855