Computer architecture

Computer architecture refers to the overall organization of a computer system. The architecture is the programmer’s view of a computer system, that have a direct impact on the logical execution of a program.

A term that is often used interchangeably with computer architecture is instruction set architecture (ISA). The ISA defines instruction formats, instruction opcodes, registers, instruction and data memory; the effect of executed instructions on the registers and memory; and an algorithm for controlling instruction execution. The ISA serves as the boundary between the software and hardware.

Computer architecture includes the following areas:
• the fundamental physical components that constitute a computer system (the hardware)
• the kind of instructions/language the computer can understand
• the underlying computer technology that manipulates these instructions (sometimes referred to as microarchitecture).

Computer architecture specifies
– Functionality of major components
– Interconnections among components

Types of Computer Architecture:
*Von-Neumann Architecture
*Harvard Architecture
*Instruction Set Architecture
*Microarchitecture
*System Design
Computer architecture

E-Wallet: Software program for electronic transaction

Many wallets today are cluttered with several cards, cash and more. The electronic wallet (e-Wallet) will provide all of the functions of today’s wallet on one convenient smart card eliminating the need for several cards.

E-wallet is a program or web service that allows users to store and control their transaction history, logins, passwords, and shipping address and credit card details, in one central place, and to retrieve these details quickly and securely for future purposes (e.g. online shopping), thus bridging the inconvenience experienced by users.

E-Wallet offers secure enrollment of the user (application download, identity check) and secure provisioning of credentials (e.g., user ID and password for wallet access). It also offers the ability for the user to securely provision and store customer-identity information (e.g., email address), payment information (e.g., credit card data), and shipping address details. The user can preselect a payment method within the wallet application to execute commerce transactions (i.e., pay merchants online, in-app, or in-store).

Electronic wallets being very useful for frequent online shoppers are commercially available for pocket, palm-sized, handheld, and desktop PCs. They offer a secure, convenient, and portable tool for online shopping.
E-Wallet: Software program for electronic transaction

Definition Of Weblogging

When Jorn Barger, an American blogger and editor of Robot Wisdom coined the term weblog, he described as the following: A weblogger logs all the other WebPages she founds interesting. It’s difficult to define of website, mainly due to diversity of models adopted for individual weblogs (also known as “blogs”).

This interesting weblog or a blog can be defined: “A web page containing brief, chronologically arranged items of information often informal diary-style text entries. A weblog can take the form of a diary, journal, what’s new page, or links to other websites.”

Weblogs can be seen as online diaries but arguably the most powerful metaphor is the ship log. Bloggers normally post fresh content related to their thoughts or opinions about specific or various topics.

Web log or blog, is a publication on the internet, therefore it has been credited with allowing people to developed online communities with a group of friends, club, society, classmates and professor, or the wider world because of how easy they are to create and of how accessible they are to anyone on the internet.
Definition of weblogging

Cyber fraud

At global level ICT advancement has immensely contributed to economic development including finance and banking.

However, it is the same ICT systems used by the banks which are negatively utilized by perpetrators of fraud. The increased use of ICT such as computers, mobile phones, internet and other associated technologies are the routes which gave rise to lot of constructive work as well as destructive work.

Cyber fraud can be defined as any embezzlement or defalcation accomplished by tampering with computer programs resulting in losses sustained by the organization, in which computer was sustained by the organization, in which computer was manipulated. Specifically, cyber fraud involves the use of internet to perpetuate fraud.

Falling victim to a cyber fraud attack can result in major financial losses, while data breaches can severely damage customers’ trust in a company. Fraudsters can easily monetise stolen information by selling it on online, and the impact of this on businesses’ reputations can be severe.
Cyber fraud

Social engineering

Social engineering is a password cracker’s use of psychological tricks on legitimate users of a computer system/network to gain the information (user names and passwords) he/she needs to gain access to a computer system network. Wikipedia defines it as “the act of manipulating people into performing actions or divulging confidential information.

Social engineering is basically a way to commit fraud in the information age or to “pull a con job” hacker style. This might involve gaining the confidence of employees with access to secure information, tricking them into thinking there is legitimate request to access secures information.

There are a great variety of attacks involving social engineering: from tricking online baking users to enter their details into a fake site, to gaining physical access to the organization through the manipulation of security guards and receptionists.

Social engineering preys on the fact that people are unable to keep up with the rapid advance of technology and little awareness of the value of information to which they have access.
Social engineering

User interface management system

In the early 1980's, the concept of a user interface management system or UIMS was an important focus area for the then-forming user interface software research community.

The term was coined after Data Base Management System (DBMS); in the same way a DBMS is a tool that helps to create and access a database, a UIMS should be a tool that helps create and utilize user interfaces.

UIMS aim at generating user interfaces based on application models and styles rules. With this approach a user interface designer is relieved from presentation details and can concentrate on design of interaction semantics.

User interface tools have made progress in producing widget sets and construction environments for designers for interfaces of standard menus, windows, boxes and buttons.

A UIMS usually provides tools to define:
*Lexicon tokens and their bindings to hardware devices
*Sequences of dialogue steps and
*The routing of tokens to appropriate semantical processing places, i.e., the interface to the application
User interface management system

Short Message Services

The Short Message Service (SMS) is a basic service allowing the exchange of short text messages between subscribers. It is a message to or from a mobile phone. It was intended to be means of exchanging limited amounts of information between two mobile subscribers.

An SMS can carry up to 140 octets of text message. The final number of characters depends on the data coding schemes used for the next part of the message. The sender can send a text message to another subscriber, and the receiver may read the message at his or her own leisure.

The first short text message is believed to have been transferred in 1992 over signaling channels of a European GSM network. Since this successful trial, SMS, usage has been the subject of tremendous growth.

Developed as part of the GSM Phase 1 ETSI technical specifications, the Short Message Service (SMS) allows mobile stations and other network connected devices to exchange short text messages.

There are two forms of SMS: Short Message Service – Point to Point (SMS-PP) and Short Message Service – Cell Broadcast (SMS-CB).
Short Message Services

Multiuser operating system

Some operating systems, in addition to being able to run multiple programs at the same time with multitasking technology, allow multiple users to sue an application simultaneously. These are known as multiuser operating systems.

In a modern multiuser operating system, a number of users located at different terminals run the same or different programs.

Multiuser operating systems are similar to many other types of operating systems. A multiuser system is almost by definition also multitasking system. On the other hand, multitasking typically refers to systems in which the tasks interact, while multiuser systems generally try to isolate the various tasks.

Most multiuser systems use preemptive, multitasking technology. A multiuser operating system must determine how to divide processor time among competing users. Various scheduling method determine which user is given access to the processor at a particular time.

When a multiuser operating system is well designed and it is running on a computer that is not overloaded, each individual user may indeed think that he has the computer all to himself. The multiuser operating system is a complex program, and requires space and time overhead.
Multiuser operating system

Multitasking operating system

A concept of managing a multitude of simultaneously active programs, competing with each other for accessing the system resources is known as multitasking. The first multitasking operating systems evolved during 1960s.

A multitasking operating system can handle multiple tasks together by applying multiprogramming techniques. Multitasking works by time slicing - that is, allowing multiple programs to use tiny slices of the processor’s time, one after the other.

When one process of a particular program has finished utilizing the CPU and is ready to I/O operations, the CPU is allocated to a process of another program which needs execution.

The multitasking operating systems are also known as by several other names, such as multiprocessing, multiprogramming, concurrent or process scheduling operating systems. Examples of multitasking operating systems are UNIX, Windows, Linus etc.

Multitasking helps in increasing the overall performance of the computer. In addition it also helps increasing the overall productivity of the user by performing a number of tasks at the same time.
Multitasking operating system

Algorithms

An algorithm is a set of instructions for solving a problem or subproblem in a finite amount of time using a finite amount of data.

It is the key concept of computer science. Two fundamental operations performed by almost every information management application are searching and sorting.

In their most basic forms, search algorithms scan through a collection to locate a particular item of interest and sort algorithms reorganize collections so they are put in particular order.

There are two basic searches for lists:
*Sequential search
*Binary search

Sequential search can be used to locate an item in any list, whereas binary search requires the list to be sorted.

Correctness is the property reflecting the extent to which the algorithm is able to reach a solution without errors. For example the sequence of actions necessary for the collection of a sum of money through ATM machines. The sequence of actions is, necessarily, prearranged and therefore any alteration of the sequence can cause an error jeopardizing its result (missing issue of banknotes, ejections of ten card, etc).

The efficiency of an algorithm is the property that regards the rapidity by which a solution is reached.
Algorithms

What is tagging?

Tagging is the flavor of the internet these days. With the explosion of social networking, an dost like Facebook, Stumble Upon, Twitter, everyone is in the mode to tag and ‘like’ content. Tagging allows individuals to use whatever terms they think are appropriate to describe an item.

Tagging roots extend back to classical Greece and the Roman Empire, when individuals would make ‘their mark’ or scratch their inscriptions on walls, which have come to known today as graffiti.

With the growing popularity of tagging, more and more tags have been collected by a variety of applications.

An item may be associated with tags describing its different aspects, such as appearance, functionality and location. It is also called keywords or tags, for future navigation, filtering, search and retrieval.

Because tagging is open-ended, tags can be just about any kind of term, they can be descriptions of the resource’s subject matter, its location, it intended use, a reminder or something else entirely.

Different people have different tagging patterns, - some people’s tags are more expressive, while others are merely descriptive.
What is tagging?

Computer system integration

The system integration process is the art and science of facilitating the marketplace of ideas that connects the many separate solutions into a system solution.

System integration is a component of the system engineering process that unifies the product components and the process components into a whole.

Systems integration can be achieved either by gluing the already existing parts together or preferably by applying an integrated top-down approach, thus coordinating all integration and development activities in a common framework.

Computer systems integration refers to integration of hardware/software systems, concepts and technologies rather than modeling industrial production methods and their implementation.

The computer system integration will achieve more efficiency and better information exchange.
Computer system integration

What is metadata?

The main distinction is that metadata is exclusive to electronic information. In computer terminology, the prefix ‘meta’ is commonly used to mean ‘about’, so a metalanguage is a language used to describe other languages, and metadata is data to describe other data.

It can be created for nay data or information resource and is routinely used to describe or provide functional information for all types of digital data.

Metadata is of paramount importance for persons, organizations and endeavors of every dimension that are increasingly turning to the World Wide Web.

It facilitates discovery of relevant information, helps in organizing electronic resources, facilitates interoperability and legacy, resource integration, provide digital identification and support archiving and preservation.

Metadata is used in traditional database management system such as relational database systems to store information on the size, structure, location, modification dates and number of tables in the database system.
What is metadata?

Typosquatting

The decline in traditional, direct cybersquatting was accompanied by a rise in a form of direct cybersquatting known as typosquatting.

In Shields v Zuccarini, an action brought against the notorious ‘typosquatter’, John Zuccarini, under the US ACPA, the US court referred to ‘typosquatting’ as:
The intentional registration of domain names that are misspellings of distinctive or famous names, causing an Internet user who makes a slight spelling or typing error to reach an unintended site…

A typosquatter attempts to cash in on the traffic generated by high volume websites. Inevitably many people will type domain names incorrectly. Once domain names started requiring annual rewards, squatters raced to grab domain named when the prior registrant failed to renew.

By 1999, squatters began ‘typosquatting’ – intentionally registering misspellings of popular websites in anticipation that users mistype these domains and reach squatters’ sites.

‘Typosquatting’ may well involve the alteration of more than one letter in a complainant’s mark. The extent to which the spelling of a domain name differs from the spelling of the complainant’s mark must therefore be considered as part of the broader inquiry into whether the domain name and the complainant’s mark are confusingly similar.

A technique known as mousetrapping was often used to profit from the visitor’s mistake. The mousetrapped visitor was trapped in a blizzard of pop-up and pop-under advertisements, often pornographic; inexperienced web surfers were often unable to extricate themselves from the mousetrap without shutting off the computer.
Typosquatting

Spam on internet

With rapid advance of internet, email has become a very important communication medium to a great many people. Within two or three years, the spam problem has grown astronomically.

Spam, also called unsolicited commercial email or ‘junk email’ aggravates many computer users. Not only can spam be nuisance but its cost may be passed onto consumers through higher charges from internet service providers who must upgrade their system to handle traffic.

Spam refers to many varieties of exploitation, malfeasance and bad behavior and spam terminology has branched out into specific sub-domains, from ‘phishing spam’ and ‘419 spam’ to splogs, linkfarms, floodbots, content farms.

Spam is not force of nature, but the product of particular populations distributed through all the world’s countries. It is mainly used for commercial promotion. Its other uses include: social activism, political campaigning, and distribution of pornographic materials.
Spam on internet

Geocomputation

Geocomputation is as much about creatively developing new data structures and algorithms for geographical analysis as it is about rigorously about testing these algorithms and methods. It is the art of using supercomputers as powerful tools for geographic science and policy.

It is a growing field of study in which computational and statistical techniques are applied to georeferenced and spatial data. Geocomputation projects often involve modeling and simulation via cellular automata, where context-specific rules for each raster cell change the cell’s state from one value to another based in surrounding cell values; visual spatial agent-based models, where populations of heterogeneous agent move, interact and sometimes also evolve in spatial landscape of networks or natural terrain and occasionally, via hybrid of each with one another or with spatially explicit systems or mathematical equations.

It is focused on the research, development and application of spatial information technologies to address social, economic and environmental problems at human and geographical scales.

Geocomputation is concerned with new computational techniques, algorithms and paradigms that are dependent upon and can take advantage of HPC (high performance computer). In fact, it involves four leading edge technologies:
*GIS, which creates the data
*Artificial intelligence (AI) and computational intelligence (CI)m which provide smart tools
*HPC, which provides the power
*Science, which provides the philosophy
Geocomputation

Cybersquatting

Cybersquatting is the act of registering a domain name that is the same as, or confusing similar to, the trademark or another and then offering to sell that domain name back to the trademark owner.

As long as the cybersquatters own the domain name, the trademark owner cannot register its own trademark as a domain name. In this sense, the cybersquatters breaches the moral right of the trademark owner to use its trademark in the digital world as his domain name.

According to US Federal Law known as Anti-Cybersquatting Consumer Protection Act, cybersquatting is registering, trafficking in or using a domain name with bad-faith intent to profit from the goodwill of a trademark belonging to someone else.

Cybersquatting is costly for businesses which must attempt to register all variations of a name to protect their domain name rights from would-be cybersquatters. Large corporations may have to register thousands of domain names across the globe just to protect their basic brands and trademarks.
A domain name is considered to be legal when the person or business who owns the name has had a legitimate business under that name for some period of time. Companies such as Christian Dior, Nike, Deutsche Bank, and even Microsoft have had to fight or pay to get the domain name corresponds to their company’s name away from cybersquatters.
Cybersquatting

Cyberstalking

Stalking behaviors range on a continuum of severity and intensity. They may begin with acts that individually may seem insignificant, such as repeated, unwanted contact in the form of telephone calls, beeper codes, e-mail messages or letters.

If left unchecked these contacts may escalate to unwanted physical contacts or the stalker’s ‘coincidental’ appearance wherever the victim goes.

Stalking and threatening a person has been a crime in the physical world for some time, and similar principles apply to online stalking. Psychologists maintain that most stalkers, whether on-line or off, are motivated by a desire to control their victims.

As in case of domestic violence, most identified offenders are make, the majority of complaining victims female.

Though researchers and law enforcement professionals have adopted a wide array of definitions, cyberstalking is most generally defined as any course of conduct that utilizes electronic communication devices to knowingly and willingly commit any of the following acts on two or more occasions, with non legitimate purpose:

*Contact or attempt to contact someone after being requested by that person to desist from contacting them.
*Persistently harass, torment or terrorize
*Steal or attempt to steal someone’s identity or information about that person, harming that person
*Make unwanted and unwarranted sexual advances toward someone
*Communicate violent intentions or threaten to cause physical injury to someone

These activities may be carried on entirely online or in connection with physical stalking or harassment.
Cyberstalking

Geographic Information System

Geographic information Systems or geographical information system (GIS) are a special class of information systems that keep track not only of events, activities and things but also of where these events, activities and things happen or exist.

GIS is a computerized mapping system designed to capture, storage, manipulate, analyze, manage, and present all types of spatial or geographical data on a computer screen.

Before GIS, researchers used films and mylars ot manually overlay spatial information. The integration of spatial information with non-spatial attributes (variable) is a critical component of GIS.

Geographic information technologies are now in common usage in high-income nations for amassing detailed information that has a stationary location in common. They are also being used for the corollary of tracking mobile individuals or objects over space and time.

GIS and related technologies are becoming more available to many users in different disciplines through the World Wide Web.
Geographic Information System

What is bus?

Bus is the name that is a vehicle of transmission of message within a higher-level protocol such as a cache coherence protocol. A single transaction within the higher-level protocol may require multiple messages on the bus.

Very often, the higher level protocol and the bus are co-designed to improve efficiency. In a personal computer, bus connects all the internal computer components to the CPU and main memory, which is called internal bus.

Bus is usually implemented on a connector, with lines of copper on a printed circuit broad or with a ribbon cable with on wire per bit.

In general there are three types of bus lines – address, data and control which respectively carry address, data and control information. Address and data may be sent over the same bus lines with additional control to indicate address or data is put on the bus.

A data bus can have any number of data lines as required by the application. However, the main characteristic of a bus is parallel data transfer.

Because all bits are transmitted at the same time over a parallel bus, data movement is extremely fast. The main benefit or parallel data transmission is its high speed.
What is bus?