Foundations Of Computing: From Hardware Essentials To Web Design GXEST203 2024 Scheme - Dr Binu V P

As a simple example, consider a program that sorts a block of numbers. To operate efficiently, the entire block of numbers must be stored in memory for the sort operation to take place, since instructions in the CPU can operate only on data in memory. Thus, it makes sense to move the entire block from disk to memory at once. For this purpose, computer systems provide a more efficient form of I/O that transfers block data directly between the I/O module and computer memory, under control of the I/O module. The transfer is initiated by a program in the CPU, using programmed I/O, but the CPU can then be bypassed for the remainder of the transfer. The I/O module will notify the CPU with an interrupt when the transfer is complete. Once this has occurred, the data is in memory, ready for the program to use. This technique of I/O–memory data transfer is known as direct memory access , or more commonly, simply as DMA. For direct memory access to take place, three primary conditions must be met...

The Internet is not a recent development but an idea that has been aroundfor more than 45 years. The concept first took shape during the early and mid-1960s and was based on the work of computer scientists at MIT and the RAND Corporation in the United States and the NPL Research Laboratory in Great Britain. The first proposal for building a computer network was made by J. C. R. Licklider of MIT in August 1962. He wrote his colleagues a memo titled (somewhat dramatically) “The Galactic Network,” in which he described a globally interconnected set of computers through which everyone could access data and software. In 1966, Roberts moved to the Advanced Research Projects Agency(ARPA), a small research office of the Department of Defense charged with developing technology that could be of use to the U.S. military. ARPA was interested in packet-switched networking because it seemed to be a more secure form of communications during wartime. ARPA funded a number of network-related research pr...

What is a Client-Server Network? A client-server network is a type of network architecture where multiple devices (clients) communicate with a central device (the server) to access resources or services. Think of it like a library system where the server is the library, and the clients are the people who come to borrow books. In this setup, the client is any device (like a computer, smartphone, or tablet) that requests information or services, and the server is the powerful computer that provides the resources, such as files, data, or applications. How Does It Work? Client Request: A client sends a request to the server. For example, when you open a website on your computer, your web browser (the client) requests the website data from a web server. Server Response: The server processes the request, retrieves the necessary data or performs the required task, and sends a response back to the client. For example, the web server sends the requested website content to your browser. Con...

Web Server: Web server is a program which processes the network requests of the users and serves them with files that create web pages. This exchange takes place using Hypertext Transfer Protocol (HTTP). Basically, web servers are computers used to store HTTP files which makes a website and when a client requests a certain website, it delivers the requested website to the client. For example, you want to open Facebook on your laptop and enter the URL in the search bar of google. Now, the laptop will send an HTTP request to view the facebook webpage to another computer known as the webserver. This computer (webserver) contains all the files (usually in HTTP format) which make up the website like text, images, gif files, etc. After processing the request, the webserver will send the requested website-related files to your computer and then you can reach the website. Different websites can be stored on the same or different web servers but that doesn’t affect the actual website that you a...

Network topology describes the fundamental layout of a network. Topology is a characteristic of all networks, large and small. It defines the path, or paths, between any two points in the network, and therefore affects the performance of the network, particularly in terms of availability, speed, and traffic congestion. There are several key network topologies, each with unique features, advantages, and disadvantages. Here’s an overview: 1.  Bus Topology In bus topology, each node is tapped into the bus along the bus. To communicate, a sending node ‘‘broadcasts’’ a message which travels along the bus. Every other node receives the message, but, because each node matches its address to that of the message, the message is ignored by every node except that of the desired recipient. Each end of the bus is equipped with a terminator to prevent signals from echoing. Branches can be added to a bus, expanding it into a tree. Messages are still broadcast through the tree. Terminators are pla...