What are Cryptocurrencies in Digital World?
Technology & Science / June 16, 2018

Cryptocurrencies have increasingly become all the rage in digital currency market. Although blockchain’s decentralise and unregulated platform has resulted in the creation of hundreds of new cryptocurrencies, this has also led to the digital currency market becoming somewhat unstable. Over the past couple of years, popular cryptocurrencies such as Bitcoin, Ethereum, Monero, and ZCash, among others saw massive fluctuations in their value. Cryptocurrency is a type of digital currency that uses cryptography for security and anti-counterfeiting measures. Public and private keys are often used to transfer cryptocurrency between individuals. Basic Overview of Cryptocurrencies A cryptocurrency is a digital or virtual currency designed to work as a medium of exchange. It uses cryptography to secure and verify transactions as well as to control the creation of new units of a particular cryptocurrency. Essentially, cryptocurrencies are limited entries in a database that no one can change unless specific conditions are fulfilled. As a counter-culture movement that is often connected to cypherpunks, cryptocurrency is essentially a fiat currency. This means users must reach a consensus about cryptocurrency’s value and use it as an exchange medium. However, because it is not tied to a particular country, its value is not controlled by a central…

What is Proxy Server, advantage & disadvantage in Networking?
Networking , Technology & Science / June 12, 2018

A computer can act on the behalf of other computers to request content from the Internet or an intranet. Proxy Server is placed between a user’s machine and the Internet. It can act as a firewall to provide protection and as a cache area to speed up Web page display. It is a computer that sits between a client computer and the Internet, and provides indirect network services to a client. It may reside on the user’s local computer, or at various points between the user’s computer and destination servers on the Internet. That intercepts all client requests, and provides responses from its cache or forwards the request to the real server. A client computer is connected to the proxy, which acknowledges client requests by providing the requested resource/data from either a specified server or the local cache memory. Client requests include files or any other resources available on various servers. Basic Overview of Proxy Server Basically proxy server plays an intermediary between the client computer and the server computer. The clients usually take the help of proxy for requesting any files, any web pages or any other resources. The proxy acts as an identification shield between the server and…

What is Distributed Shared Memory in Computer System?
Technology & Science / May 2, 2018

In parallel and distributed applications there are two common programming models for inter-process communication: shared memory and message passing. Shared memory has been the standard for tightly-coupled systems (multiprocessors), where the processors have uniform access to a single global memory. A large progress was recently made in the research and development of systems with multiple processors, capable of delivering high computing power in order to satisfy the constantly increasing demands of typical applications. Overview of Distributed Shared Memory Distributed shared memory (DSM) systems simplify the task of writing distributedmemory parallel programs by automating data distribution and communication. Unfortunately, DSM systems control memory and communication using fixed policies, even when programmers or compilers could manage these resources more efficiently. Distributed shared memory is an attempt to merge the ease of programming of shared memory, with the scalability of distributed memory architectures. Hiding the distribution aspects of an architecture for the programmer eases programming and especially porting existing, applications. DSM systems exist in a large number and with very varying behavior. Distributed shared memory (DSM) is an abstraction used for sharing data between computers that do not share physical memory. Processes access DSM by reads and updates to what appears to be…

What is Simple Mail Transfer Protocol (SMTP)?
Networking , Technology & Science / April 29, 2018

Simple Mail Transport Protocol is the most widely adopted protocol for e-mail delivery. Simple Mail Transport Protocol (SMTP) was originally designed for a smaller community of users which was assumed to be well behaved and trust worthy. As such no heed was paid towards incorporating security protocols in it. But with its growth, this trust was breached, owing to lack of adequate security mechanism in it. Email is emerging as the one of the most valuable service in internet today. Most of the internet systems use SMTP as a method to transfer mail from one user to another. Description about SMTP SMTP stands for Simple Mail Transfer Protocol. This protocol allows transmitting electronic mail over the Internet or any other network. The protocol itself is designed on a character basis. Thus the entire transfer of a mail can be exanimated by a human being without having to decode first the data. This is the reason why mails can be send without major problem using a simple Telnet application. The entire process of sending a mail is describe here using a Telnet application as example base. Most e-mail systems that send mail over the Internet use simple mail transfer protocol (SMTP)…

What is Distributed File System in Distributed System
Technology & Science / April 25, 2018

In the modern world, there is a growing need for collaboration among geographically separated groups. Platforms and services that assist such collaboration are in great demand. Applications that process large volumes of data require a backend infrastructure for storing data. The distributed file system is the central component for storing data infrastructure. The purpose of a distributed file system (DFS) is to allow users of physically distributed computers to share data and storage resources by using a common file system Overview of Distributed File System A distributed file system is a system which enables set of program to access and store files which are distributed across the boundaries. The system also allow user to find records from any machine in the network across the globe. The performance of the system can be compared with the local file system. The distributed file systems are responsible for various tasks like organizing of files, storage, extract, sharing, naming and security of records and files. This system provides abstraction that hides everything from the user and provides all concerns of the programmers. The files are stored in a specific structure on disks or other non – volatile devices. They have various provisions like creating,…

What is Access Control in Network?

The need for network security is a relatively new requirement. Security incidents are rising at an alarming rate every year. As the complexity of the threats increases, so do the security measures required to protect networks. Information Systems are decomposed in three main portions, hardware, software and communications with the purpose to identify and apply information security industry standards, as mechanisms of protection and prevention, at three levels or layers: Physical, personal and organizational. Overview of Access Control Access control is generally a policy or procedure that allows, denies or restricts access to a system. It may, as well, monitor and record all attempts made to access a system. Access Control may also identify users attempting to access a system unauthorized. It is a mechanism which is very much important for protection in computer security. Access control approaches determine how users interact with data and other network resources. Furthermore, access control measures ensure data are protected from unauthorized disclosure or modification. Access control is the traditional center of gravity of computer security. It is where security engineering meets computer science. Its function is to control which principals have access to which resources in the system—which files they can read, which…

Commonwealth Games
Sports / April 6, 2018

History In 1891, John Astley Cooper first wrote about a sporting competition that would bring organized members of the British Empire, but it wasn’t until 1911, at the coronation of King George V, that an ‘Inter-Empire Championships’ was held. This occasion included teams from Australasia, Canada, South Africa and the United Kingdom. They competed in athletics, boxing, wrestling and swimming events. The first official Commonwealth Games (called the British Empire Games) were held in 1930 in Hamilton, Canada. Four hundred athletes from 11 countries competed in 59 events across six sports: athletics, boxing, lawn bowls, rowing, aquatics (swimming and diving) and wrestling. Interestingly, women only competed in swimming events. The competing nations were: Australia, Bermuda, British Guyana, Canada, England, Northern Ireland, Newfoundland, New Zealand, Scotland, South Africa and Wales. Since then, the Games have been conducted every four years (except for 1942 and 1946 due to World War II) and the event has seen many changes, not least in its name. From 1930 to 1950 the Games were known as the British Empire Games, from 1954 until 1966 the British Empire and Commonwealth Games, and from 1970 to 1974 they took on the title of British Commonwealth Games. It was the 1978 Games…

What is Correlation Coefficient?
Technology & Science / April 1, 2018

Many statistical analyses can be undertaken to examine the relationship between two continuous variables within a group of subjects. Two of the main purposes of such analyses are: Correlation coefficients are used in statistics to measure how strong a relationship is between two variables. To assess whether the two variables are associated. There is no distinction between the two variables and no causation is implied, simply association. To enable the value of one variable to be predicted from any known value of the other variable. One variable is regarded as a response to the other predictor (explanatory) variable and the value of the predictor variable is used to predict what the response would be. Correlation coefficient is a measure of association between two variables, and it ranges between –1 and 1. If the two variables are in perfect linear relationship, the correlation coefficient will be either 1 or –1. The sign depends on whether the variables are positively or negatively related. The correlation coefficient is 0 if there is no linear relationship between the variables. Two different types of correlation coefficients are in use. One is called the Pearson product moment correlation coefficient, and the other is called the Spearman rank…

What is a Confusion Matrix in Machine Learning?

What is Confusion Matrix? In the field of machine learning and specifically the problem of statistical classification, a confusion matrix, also known as an error matrix. A confusion matrix represents information about actual and classified cases produced by a classification system. Performance of such a system is commonly evaluated by demonstrating the correct and incorrect patterns classification. A confusion matrix is a table that is often used to describe the performance of a classification model (or “classifier”) on a set of test data for which the true values are known. It allows the visualization of the performance of an algorithm. A confusion matrix (Kohavi and Provost, 1998) contains information about actual and predicted classifications done by a classification system. Performance of such systems is commonly evaluated using the data in the matrix. The following table shows the confusion matrix for a two class classifier. It allows easy identification of confusion between classes e.g. one class is commonly mislabeled as the other. Most performance measures are computed from the confusion matrix. The entries in the confusion matrix have the following meaning in the context of our study: TN is the number of correct predictions that an instance is negative, FP is the number of incorrect predictions…

What is Secure Socket layer (SSL) and How it Secure the Network

The boom of internet, web technologies bring the whole world under a single roof. Transferring information through e-ways leads security to be an important aspect to deal with. In recent years, there has been tremendous development in Internet. Right from retrieving information about any subject, you can use Internet for many purposes. But when two parties like client and a server are communicating over the Internet. Secure Socket layer (SSL) is vital to Web security. It provides a strong sense of confidentiality, message integrity, and server authentication to users. Overview of SSL SSL stands for Secure Sockets Layer protocol developed by Netscape and is the standard Internet protocol for secure communications. SSL (Secure Sockets Layer) is a standard security protocol for establishing an encrypted link between a server and a web browser. This link ensures that all data exchanged between the browser and the server remains secure. SSL allows your website and your visitor’s browser to transmit private, sensitive information without the worry of eavesdropping, web forgery, and data tampering. The main role of Secure Socket layer (SSL) is to provide security for Web traffic. Security includes confidentiality, message integrity, and authentication. SSL achieves these elements of security through the…

Insert math as
Block
Inline
Additional settings
Formula color
Text color
#333333
Type math using LaTeX
Preview
\({}\)
Nothing to preview
Insert