Natalie Chalk AS computing: September 2011

Tuesday, 27 September 2011

3.2.5 structure of the internet

Internet - An interconnected system of networks that connects computers around the world via IP addresses. It is broken into packets, across many possible paths from computer to computer.

Web - Part of the internet which reffers to the text, graphics and multi media. They are structured using HTML and transporting using HTTP.

Intranet - A local or restricted communications network, esp. a private network created using World Wide Web software.

Extranet - An intranet that can be partially accessed by authorized outside users, enabling businesses to exchange information over the Internet securel.

Packet - A part of a larger peice of information (e.g a web page, a document, an MP3) It contains: A header (where it came from, where its going)
Payload (actual information)
Trailor (info to allow for error checking)

Router - A device that forwards data packets to the appropriate parts of a computer network.

Domain name - The last three letters in a domain name indicate what type of organization owns the address: for instance, .com stands for commercial, .edu for educational, and .org for nonprofit.

IP address - A unique number and every computer has one. It is composed of 4 sets of 3 digit numbers.

Domain Name Server - These are special computers that translate human-friendly URLs into computer-friendly IP addresses. This process takes place every time a user requests a page from a website.

Internet registries and registrars - Internet registires mangages lots of IP addresses in parts of the world. Internet registrars manage the allocation of domain names.

ISP - An Internet service provider (ISP) is a company that provides access to the Internet. Access ISPs directly connect customers to the Internet using copper wires, wireless or fiber-optic connections.

URI - Unifrom resource identifier - provides a unique identification

URN - Unique name for something

URL - Uniform resource locator - Unique location for something

Client - A computer on a network using resouces provided by another computer

Server - A computer on a network providing resources to lots of other computers.

TCP/IP - The two protocols that work together to move information around the internet

Wednesday, 21 September 2011

Homework 22/09/2011

1. HTML - Hypertext marked language. It is written in the form of HTML elements which include tags enclosed in angle brackets within the webpage.

2. The tags we need to know for the exam are
<strong> </strong> which would make the text bold
<em> </em> this would make the text italic
<head> </head>
<body> </body>
<h1> </h1> this determins the font size
<p> </p> this is for the start and end of a paragraph
<ol> </ol> this is for an ordered list
<ul> </ul> this is for an un ordered list
<li> </li> this is for a list item
<a href="http://www.facebook.com">click here</a> this is for a hyperlink (taking you to another website)

CSS means Cascading style sheets. To change the way HTML will look in the brouser you add
some style to it with CSS. For example, styling backgrounds, styling text, styling fonts and
styling lists.
For example

<p style=“font-size:small; colour:purple" >Hello

Thursday, 8 September 2011

Homework

ICT deals more with the organisational and business side of IT systems, and the theory behind good data, types of information and information flows. You study topics like the Nature of Information, Role of IT in Organisations, and Management Information Systems. Also, ICT is softer - but wasn't supposed to be originally - it was supposed to cover telecommunications subjects that weren't covered by 'traditional' studies in computer science that taught programming and software engineering. ICT can cover routing and configuration - or at least that was the idea. But if you want to be a real 'techie' I'd suggest doing Computing. It depends what interests you - computing science will always be more in depth and for people who are happier working on difficult mathematical problems rather than organisational ones. Beware though - skills in computing can get outdated pretty sharpish and you'll be upgrading your skills annually for the rest of your career. Computing is a lot more technical, with less emphasis on business and more emphasis on the actual design and programming of IT systems. Also computing involves a lot of maths, and unlike ICT, you will actually be expected to learn how to use a number of programming languages. Topics include things such as Networking, Hardware and Operating Systems.

Cloud computing.

Not too long ago, one of the leading computer companies filed an application to trademark the term ‘cloud computing’, which was denied by the US Patent and Trademark Office. That was in August 2008 when cloud computing was in its infancy. Yet that act was a kind of starting line: since then, cloud computing has received a lot of attention.

The economic downturn most likely provided an impetus to jumpstart cloud computing. The potential is huge. Cloud computing could transform the IT industry from an asset-centric approach to a services-centric approach. It could change IT from on-premise technology to on-demand services.

The last two years saw tremendous innovation and progress, especially in the ‘Infrastructure-as-a-Service’ realm. Because of the low utilization of servers and the introduction of virtualization layer and related software, server virtualization took off. What started off as a concept concerning the virtualization of servers has extended to include network virtualization, desktop virtualization and application virtualization.

Amazon, a retail giant, has quietly become a big player in the IT industry through innovation. The growth of this industry has not been without some setbacks. There has been the publicized outage of Amazon EC2 and the Sony Playstation network data breach.

Tuesday, 6 September 2011

Blog post

testing!!!!!!!!!!!!!!!!! testing!!!!!!!!!!! 123 sat next to ashwee