EXERCISE N° 1: LINUX

Warm Up To Penguins The Zen Of Xen One of the hottest recent topics in the computer industry at this time is virtualization. Products such as VMware and Microsoft’s Virtual PC are trying to take advantage of the increasing demand to run virtual computers on top of a physical host. There are several reasons to do this. If, for example, you need to run a number of different versions of Linux from time to time, you can run them as virtual systems on top of a stable host without worrying about constantly reinstalling or corrupting your system. For businesses, virtual machines let many users share a single physical host. Because a system rarely runs at 100% load all the time, you can usually load-balance and get more bang for your hardware buck with virtual systems. Linux, of course, has a virtualization application, too: Xen. Xen is an open-source project organized by XenSource which is in turn owned by Citrix, known for GotoMyPC among others. Xen consists of a hypervisor, which is simply a software package that enables virtual hosts to run on Linux, and the virtual hosts themselves. If you’ve ever used VMware, there are some significant differences between how VMware (and Virtual PC) handles virtualization and how Xen does it. For example, VMware runs as a program (or service) that the virtual hosts run inside, but Xen actually is part of the Linux Kernel. The “host” machine is just another virtual machine (or domain, as Xen calls them) running on the hardware. Although this may seem a bit strange conceptually, it seems to pay off performance-wise.

http://www.computerpoweruser.com/

REVIEW 2- SIMPLE PAST: HISTORY OF COMPUTING

HISTORY OF COMPUTING

Computing hardware has been an important component of the process of calculation and data storage since it became useful for numerical values to be processed and shared.

Devices to aid computation changed from simple recording and counting devices to the abacus, the slide rule, analog computers, and more recent electronic computers. Even today, an experienced abacus user using a device hundreds of years old can sometimes complete basic calculations more quickly than an unskilled person using an electronic calculator — though for more complex calculations, computers out-perform even the most skilled human.

This article covers major developments in the history of computing hardware, and attempts to put them in context. For a detailed timeline of events, see the computing timeline article. The history of computing article is a related overview and treats methods intended for pen and paper, with or without the aid of tables.

As early as 1725 Basile Bouchon used a perforated paper loop in a loom to establish the pattern to be reproduced on cloth, and in 1726 his co-worker Jean-Baptiste Falcon improved on his design by using perforated paper cards attached to one another for efficiency in adapting and changing the program. The Bouchon-Falcon loom was semi-automatic and required manual feed of the program.

In 1801, Joseph-Marie Jacquard developed a loom in which the pattern being woven was controlled by punched cards. The series of cards could be changed without changing the mechanical design of the loom. This was a landmark point in programmability.

Herman Hollerith invented a tabulating machine using punched cards in the 1880s.
In 1833, Charles Babbage moved on from developing his difference engine to developing a more complete design, the analytical engine, which would draw directly on Jacquard's punched cards for its programming.

In 1890, the United States Census Bureau used punched cards and sorting machines designed by Herman Hollerith, to handle the flood of data from the decennial census mandated by the Constitution. Hollerith's company eventually became the core of IBM. IBM developed punched card technology into a powerful tool for business data-processing and produced an extensive line of specialized unit record equipment. By 1950, the IBM card had become ubiquitous in industry and government. The warning printed on most cards intended for circulation as documents (checks, for example), "Do not fold, spindle or mutilate," became a motto for the post-World War II era.

BLU-RAY DISC (Translation)

BLU-RAY DISC

Blu-ray, also known as Blu-ray Disc (BD), is the name of a next-generation optical disc format jointly developed by the Blu-ray Disc Association (BDA), a group of the world's leading consumer electronics, personal computer and media manufacturers (including Apple, Dell, Hitachi, HP, JVC, LG, Mitsubishi, Panasonic, Pioneer, Philips, Samsung, Sharp, Sony, TDK and Thomson). The format was developed to enable recording, rewriting and playback of high-definition video (HD), as well as storing large amounts of data. The format offers more than five times the storage capacity of traditional DVDs and can hold up to 25GB on a single-layer disc and 50GB on a dual-layer disc. This extra capacity combined with the use of advanced video and audio codecs will offer consumers an unprecedented HD experience. While current optical disc technologies such as DVD, DVD±R, DVD±RW, and DVD-RAM rely on a red laser to read and write data, the new format uses a blue-violet laser instead, hence the name Blu-ray. Despite the different type of lasers used, Blu-ray products can easily be made backwards compatible with CDs and DVDs through the use of a BD/DVD/CD compatible optical pickup unit. The benefit of using a blue-violet laser (405nm) is that it has a shorter wavelength than a red laser (650nm), which makes it possible to focus the laser spot with even greater precision. This allows data to be packed more tightly and stored in less space, so it's possible to fit more data on the disc even though it's the same size as a CD/DVD. This together with the change of numerical aperture to 0.85 is what enables Blu-ray Discs to hold 25GB/50GB. Blu-ray is currently supported by more than 180 of the world's leading consumer electronics, personal computer, recording media, video game and music companies. The format also has broad support from the major movie studios as a successor to today's DVD format. In fact, seven of the eight major movie studios (Disney, Fox, Warner, Paramount, Sony, Lionsgate and MGM) have released movies in the Blu-ray format and six of them (Disney, Fox, Sony, Warner, Lionsgate and MGM) are releasing their movies exclusively in the Blu-ray format. Many studios have also announced that they will begin releasing new feature films on Blu-ray Disc day-and-date with DVD, as well as a continuous slate of catalog titles every month. For more information about Blu-ray movies, check out our Blu-ray movies and Blu-ray reviews section which offers information about new and upcoming Blu-ray releases, as well as what movies are currently available in theBlu-ray format.

Source: www.wikipedia.org.com

COMPUTER ARCHITECTURE

In computer engineering, computer architecture is the conceptual design and fundamental operational structure of a computer system. It is a blueprint and functional description of requirements (especially speeds and interconnections) and design implementations for the various parts of a computer — focusing largely on the way by which the central processing unit (CPU) performs internally and accesses addresses in memory.
It may also be defined as the science and art of selecting and interconnecting hardware components to create computers that meet functional, performance and cost goals.

Computer architecture comprises at least three main subcategories:
Instruction set architecture, or ISA, is the abstract image of a computing system that is seen by a machine language (or assembly language) programmer, including the instruction set, memory address modes, processor registers, and address and data formats.Microarchitecture, also known as Computer organization is a lower level, more concrete, description of the system that involves how the constituent parts of the system are interconnected and how they interoperate in order to implement the ISA[2]. The size of a computer's cache for instance, is an organizational issue that generally has nothing to do with the ISA.
System Design which includes all of the other hardware components within a computing system such as: system interconnects such as computer buses and switches memory controllers and hierarchies
CPU off-load mechanisms such as direct memory Access issues like multi-processing.
Once both ISA and microarchitecture has been specified, the actual device needs to be designed into hardware. This design process is often called implementation. Implementation is usually not considered architectural definition, but rather hardware design engineering.
Implementation can be further broken down into three pieces:
Logic Implementation/Design - where the blocks that were defined in the microarchitecture are implemented as logic equations.
Circuit Implementation/Design - where speed critical blocks or logic equations or logic gates are implemented at the transistor level.
Physical Implementation/Design - where the circuits are drawn out, the different circuit components are placed in a chip floor-plan or on a board and the wires connecting them are routed.
For CPUs, the entire implementation process is often called CPU design.
More specific usages of the term include more general wider-scale hardware architectures, such as cluster computing and Non-Uniform Memory Access (NUMA) architectures.