Selasa, 2 November 2010

KARNIVAL iCT











UBUNTU



Ubuntu (pronounced /uːˈbuːntuː/[4][5] or /uːˈbʌnˌtuː/[citation needed]) is a computeroperating system originally based on the Debian GNU/Linux distribution and distributed as free and open source software with additional proprietary software available.
It is named after the Southern African philosophy of Ubuntu ("humanity towards others").[6] Ubuntu is designed primarily for desktop usage, though netbook andserver editions exist as well.[7] Web statistics suggest that Ubuntu's share of Linux desktop usage is about 50 percent,[8][9] and upward trending usage as a web server.[10]
Ubuntu is composed of many software packages, of which the vast majority are distributed under a free software license (also known as open source). The main license used is the GNU General Public License (GNU GPL) which, along with theGNU Lesser General Public License (GNU LGPL), explicitly declares that users are free to run, copy, distribute, study, change, develop and improve the software. Ubuntu is sponsored by the UK-based company Canonical Ltd., owned by South African entrepreneur Mark Shuttleworth. Canonical creates revenue by sellingtechnical support and services tied to Ubuntu.
Canonical endorses and provides support for three additional Ubuntu-derived operating systems: Kubuntu, Edubuntu, also known as Ubuntu Education Edition, and Ubuntu Server Edition. There are several other derivative operating systems including local language and hardware-specific versions.[11]
Canonical releases new versions of Ubuntu every six months and supports Ubuntu for eighteen months by providing security fixes, patches to critical bugs and minor updates to programs. LTS (Long Term Support) versions, which are released every two years,[12] are supported for three years on the desktop and five years for servers.[13] The latest version of Ubuntu, 10.10 (Maverick Meerkat), was released on October 10, 2010.

Ahad, 27 Jun 2010

Virus H1N1


Influenza A (H1N1) virus is a subtype of influenza A virus and was the most common cause of human influenza (flu) in 2009. Some strains of H1N1 are endemic in humans and cause a small fraction of all influenza-like illness and a small fraction of all seasonal influenza. H1N1 strains caused a few percent of all human flu infections in 2004–2005.[1] Other strains of H1N1 are endemic in pigs (swine influenza) and in birds (avian influenza).
In June 2009, the World Health Organization declared the new strain of swine-origin H1N1 as a pandemic. This strain is often called swine flu by the public media. This novel virus spread worldwide and had caused about 17,000 deaths by the start of 2010.

Ahad, 20 Jun 2010


In computer networking, topology refers to the layout of connected devices.
Network topology is defined as the interconnection of the various elements (links, nodes, etc.) of a computer network.[1][2] Network Topologies can be physical or logical. Physical Topology means the physical design of a network including the devices, location and cable installation. Logical topology refers to the fact that how data actually transfers in a network as opposed to its physical design.
Topology can be considered as a virtual shape or structure of a network. This shape actually does not correspond to the actual physical design of the devices on the computer network. The computers on the home network can be arranged in a circle shape but it does not necessarily mean that it presents a ring topology.
Any particular network topology is determined only by the graphical mapping of the configuration of physical and/or logical connections between nodes. The study of network topology uses graph theory. Distances between nodes, physical interconnections, transmission rates, and/or signal types may differ in two networks and yet their topologies may be identical.
A Local Area Network (LAN) is one example of a network that exhibits both a physical topology and a logical topology. Any given node in the LAN has one or more links to one or more nodes in the network and the mapping of these links and nodes in a graph results in a geometrical shape that may be used to describe the physical topology of the network. Likewise, the mapping of the data flow between the nodes in the network determines the logical topology of the network. The physical and logical topologies may or may not be identical in any particular network.

Network architecture is the design of a communications network. It is a framework for the specification of a network's physical components and their functional organization and configuration, its operational principles and procedures, as well as data formats used in its operation.
In computing, the network architecture is a characteristics of a computer network. The most prominent architecture today is evident in the framework of the Internet, which is based on the Internet Protocol Suite.
In telecommunication, the specification of a network architecture may also include a detailed description of products and services delivered via a communications network, as well as detailed rate and billing structures under which services are compensated.
In distinct usage in distributed computing, network architecture is also sometimes used as a synonym for the structure and classification of distributed application architecture, as the participating nodes in a distributed application are often referred to as a network. For example, the applications architecture of the public switched telephone network (PSTN) has been termed the Advanced Intelligent Network. There are any number of specific classifications but all lie on a continuum between the dumb network (e.g., Internet) and the intelligent computer network (e.g., the telephone network). Other networks contain various elements of these two classical types to make them suitable for various types of applications. Recently the context aware network, which is a synthesis of the two, has gained much interest with its ability to combine the best elements of both.

Computer Network


A computer network, often simply referred to as a network, is a collection of computers and devices connected by communications channels that facilitates communications among users and allows users to share resources with other users. Networks may be classified according to a wide variety of characteristics. This article provides a general overview of types and categories and also presents the basic components of a network.