Internet Architecture Give me file x Here it

Internet Architecture Give me file x Here it is Desktop computer “client” Computer on the Internet holding information remote “server”

Internet Services • The World Wide Web or a system of interlinked hypertext documents accessed via the Internet (multiple delivery options) • Search tools via WWW (search engines, databases, gateways and portals) • Communication (E-mail) • Retrieval/information transfer (File Transfer Protocol - FTP)

The World-Wide Web • WWW, web, W 3, World-Wide Web • Often what people mean by the Internet • Based on hypertext - the ability to link text and documents dynamically and interactively • Uses hypertext markup language - HTML • The WWW is a global standard • Can use text, graphics, sound and video • Anyone can link to and make use of the web

Delivery: Dial Up Connection DIAL-UP CONNECTION International Gateway Link Phone Line Internet Client Computer ISP Server With Modem • Speed of line • Quality of line • Speed of connection – modem speed: usually 56 kilobytes per second – dial into Internet Service Provider (ISP) – quality of telephone line

Delivery: Broadband Connection FULL – TIME CONNECTION Leased Line Permanent Connection Local Area LAN Server • Speed of line • Quality of line Network • Speed of connection – LAN Server speed – Bandwidth (minimally 256 kbts/s to 1. 0 Mbit/s) – Mode of link (radio, leased line, satellite) LAphone line Internet

Access Speed Issues • Cables vary in speed and amount of information they can carry • Sometimes cables are slow in carrying information or lose the signal, especially if: irmation must cross long distances too much traffic on the cable capacity, or bandwidth, is low – information must cross long distances – too much traffic on cable – cable capacity, or bandwidth, is low

Web Browser • Browser is the software that is used to view the Web • Standard browser features – scrolling, back, forward, stop, home, refresh • Navigation - in built features – back, forward, home, go to, yes, no • Search on a single web page • Multiple Web browser windows

http: //www. Mozilla. com/Firefox

Browser Customization • • Toolbar options Link to a specific homepage Using the right click mouse button Using favorites or bookmarks – Adding – Organizing – Editing

Internet Requirements for HINARI • 128 kbps, local area network (LAN), or cable connection required. • A hard-wired full-time Internet connection (T 1 or better) enables the fastest downloads. • Satellite or network connections, though slower, are also adequate. • Web Browser - Internet Explorer version 4. 0 or higher OR Mozilla Firefox 1. 0 or higher or (Google) Chrome 1. 0

Adobe Reader for PDFs • You will need an Adobe Reader to view journal articles in PDF (Portable Document Format). • Adobe Reader can be downloaded for FREE from the Adobe web site: http: //www. adobe. com/products/acrobat/readstep 2. html

This page contains the link to download option for Adobe Reader version 8. 1. 2 This is viewed using the Mozilla Firefox web browser.

The Internet Address or URL This page is being viewed in the Mozilla Firefox Browsers allow computers to read Hyper Text Mark-up Language OR HTML. The Address or URL is typed in here.

Entering a URL address in the address box After entering a URL or Internet address in the address box, hit the ENTER or RETURN key. In this example we have entered the URL http: //www. who. int/hinari/ - for the HINARI website.

Hypertext links Links to other pages are usually underlined or in another colour of text.

Forward and back navigation buttons The arrow buttons on the tool bar allow users to move Back and Forward to pages within the website.

Home page button The House icon on the tool bar will take you back to the browser’s default Home Page.

This is the end of Module 1. 1 There is a Work Book to accompany this part of the module. The workbook will take you through a live session covering the topics included in this demonstration with working examples. Updated 03 2009