Mobilecompt 2
Mobilecompt 2
Mobilecompt 2
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A PAPER PRESENTATION ON
Abstract
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Introduction
What is mobile computing?
A view on portable devices.
Applications
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Introduction
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 place, anytime, and anywhere.
Ubiquitous computing and nomadic computing are synonymous with mobile computing.
Mobile computing helps users 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 users 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 palm top computers give mobile users access to diverse
sources of global information anywhere 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 a 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 marketplace.
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The pen interface allows users to interact with the computer in a very natural and 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 options from scrolling
lists and checkboxes.
Mobile computing applications can closely simulate the original paper form,
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 access to printers, barcode readers, and various
other peripheral devices.
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Laptops are typically used and supported in the same way as desktop PCs. In fact, many
organizations have replaced desktops with their portable cousins, as the workforce 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 PCs
were. That is, adventurous early adopters buy the devices for their personal use and then ask
IT departments to integrate the devices into 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 Web sites 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, and
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 (FedEx) and the
United Parcel Service (UPS) delivery personnel 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 10-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 (LANs), 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 (e.g., a bridge can
connect an Ethernet and Token-Ring network).
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Low Bandwidth
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 required to improve effective bandwidth usage include data compression logging
requests to combine multiple short ones, lazy write back, difference-based updates, caching,
prefetching, usage of proxy, priority scheduling, etc.
power Limitations
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 battery weight. In addition, efficient software operations can
help to lower the power consumption. Examples include: shifting the processing to a fixed
host, aggressively caching and prefetching data to reduce disk traffic, and transmitting less
data while receiving more
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Security
Security and privacy 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 is encryption. In personal profiles of users
are used to restrict access to the mobile units.
Limited Capabilities
Unlike stationary computers, mobile computers are smaller in physical size and have smaller
storage capacity. PDA’s like Info pad and ParcTab are designed to have extreme portability
and provide ubiquitous information access. However, their applications rely heavily on the
interoperability of the pads and other servers. Even ordinary laptops typically have less RAM
and smaller hard disks than stationary computers.
To overcome these limitations, some useful techniques are proposed including: Compressing
file systems, accessing remote storage over the network, sharing code libraries and
compressing virtual memory pages. In addition, the user interface has to be designed to adapt
to the small screen size of the portable computers.
Disconnection
Disconnection can 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, prefetching 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 reconcile any update conflicts made by various clients. It also uses concurrency
control and prefetching techniques. However, this approach is designed mainly for file
systems and does not work for all kinds of applications.
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Mobility
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.
Merits
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:
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Demerits
Consumer Goods. Typical applications include inventory, merchandising, order entry, and
sales automation. Features found in these applications usually provide access to stock and
pricing information, monitor promotions, and perform shelf space analysis including number
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of facings and product age. Customer detail helps reps to act more as consultants than order
takers.
Delivery & Route Sales. With fierce competition and an increasing inventory, having timely
and accurate information is more important than ever.
Government. 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, commercial and residential buildings).
Healthcare. 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.
Market Research. Automating the survey process has enabled these companies to get their
data more accurately and quickly while being able to customize their queries at will.
Pharmaceuticals. In addition to the reps need to perform account management and call
reporting functions, the FDA’s requirement for physician signatures for all drug samples
dispensed was an added complication that was eliminated through the use of mobile
technology.
Utilities. Eliminating the rekeying of data and providing a means to perform on site analysis
are instrumental to an industry that is required to perform inspections on a routine basis
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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 community's. 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. Its mobile computing jungle where old
technologies must evolve to survive and where proponents of new technologies are jockeying
for dominance. It is a dangerous and exciting time where existing business models can
crumble and more nimble, innovative companies can usurp established institutions.
Conclusion
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 the banes of mobile computing the security level should be improved.
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Bibilography
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