Yonas Tibebu

The precise manner in which data is organised on a hard disk drive is determined by the file system used. File systems are generally operating system dependent. However, since it is the most widely used PC operating system, most other operating systems’ file systems are at least read-compatible with Microsoft Windows. The FAT file system was first introduced in the days of MS-DOS way back in 1981. The purpose of the File Allocation Table is to provide the mapping between clusters – the basic unit of logical storage on a disk at the operating system level – and the physical location of data in terms of cylinders, tracks and sectors – the form of addressing used by the drive’s hardware controller.  The FAT contains an entry for every file stored on the volume that contains the address of the file’s starting cluster. Each cluster contains a pointer to the next cluster in the file, or an end-of-file indicator at (0xFFFF), which indicates that this cluster is the end of the file...

Under development for years and in use for reported thousands (maybe more), the definition of this ‘secret Internet has been elusive as its evolution is user-defined and built. This shifting innovation landscape results in frequent new concepts on how to apply Darknet technology and further navigate the future of cloaked or otherwise ‘deep’ network relations. As defined by Wikipedia: “A Darknet is an overlay network that can only be accessed with specific software, configurations, or authorization, often using non-standard communications protocols and ports. The purpose of of darknets is motivated by the desire to hide content, or even the existence of data and communication, from competing business or government interests. The most widespread darknets are governmental and corporate intranets, the use of which is a standard security practice nowadays, friend-to-friend networks (usually used for file sharing with a peer-to-peer connection) and privacy networks such as Tor.” The no...

You click to check out at an online merchant. Suddenly your browser address bar says HTTPS  instead of HTTP. What's going on? Is your credit card information safe? Good news. Your information is safe. The website you are working with has made sure that no one can steal your information. Instead of HyperText Transfer Protocol (HTTP), this website uses  HyperText Transfer Protocol Secure . Using HTTPS, the computers agree on a "code" between them, and then they scramble the messages using that "code" so that no one in between can read them. This keeps your information safe from hackers. They use the "code" on a  Secure Sockets Layer (SSL) , sometimes called Transport Layer Security (TLS) to send the information back and forth. How Does HTTP Work? In the beginning, network administrators had to figure out how to share the information they put out on the Internet. They agreed on a procedure for exchanging information and called it HyperT...

Research can be classified in many different ways on the basis of the methodology of research, the knowledge it creates, the user group, the research problem it investigates etc,. BASIC RESEARCH The research which is done for knowledge enhancement, the research which does not have immediate commercial potential. The research which is done for human welfare, animal welfare and plant kingdom welfare. It is called basic, pure, fundamental research. The main motivation is to expand man's knowledge, not to create or invent something. APPLIED RESEARCH Applied research is designed to solve practical problem of the modern world, rather than to acquire knowledge for knowledges sake. The goal of applied research is to improve the human condition. It focus on analysis and solving social and real life problems. This research is generally conducted on large scale basis, it is expensive. As such, it often conducted with the support of some financing agency like government, public corpo...

SRAM : Static random access memory uses multiple transistors, typically four to six, for each memory cell but doesn't have a capacitor in each cell. It is used primarily for  cache . The following are some common types of RAM: ·          DRAM :  Dynamic random access memory  has memory cells with a paired transistor and  capacitor  requiring constant refreshing. ·          FPM DRAM :  Fast page mode dynamic random access memory  was the original form of DRAM. It waits through the entire process of locating a bit of data by column and row and then reading the bit before it starts on the next bit. Maximum transfer rate to L2 cache is approximately 176 MBps. ·          EDO DRAM :  Extended data-out dynamic random access memory  does not wait for all of the processing of the first bit before continuing to the next one. ...

The Internet is the most commonly and widely used computer network, but it isn't the only type of computer network for sharing information digitally. The Internet, an intranet and an extranet are three similar, but distinct types of networks. While the Internet is open to anyone and everyone, intranets and extranets are designed for smaller groups of people. Think of the latter two as larger versions of a personal home network. Internet The Internet is a network that is available to anyone with an Internet-connected device. It is a massive collection of networks sharing information publicly in the form of interlinked Web pages. Internet Protocol defines a site's unique location which most users see as a domain name or URL. The network is literally world-wide and is often referred to as the world wide web. Intranet An intranet network is only available to a small group of people. Intranets are mainly used within businesses and organizations to provide access to files...

The heart of managing the processor comes down to two related issues: ·          Ensuring that each process and application receives enough of the processor's time to function properly ·          Using as many processor cycles as possible for real work The basic unit of software that the operating system deals with in scheduling the work done by the processor  is either a  process  or a  thread , depending on the operating system. It's tempting to think of a process as an application, but that gives an incomplete picture of how processes relate to the operating system and hardware. The application you see (word processor, spreadsheet or game) is, indeed, a process, but that application may cause several other processes to begin, for tasks like communications with other devices or other computers. There are also numerous processes that run without giving you direct evidence that ...