FreeAsAir

Access the Internet

What is the Internet?

  • Worldwide groups of connected networks that allows the public to access information, send messages, obtain products/services
  • Networks use the same ‘language’
  • Use the same protocols (rules)
  • ‘plat form- independent’
  • Protocols devised so that can be understood by all main computer platforms

Connecting to the Internet

ISP

  • Has a server which is permanently online and has a permanent internet address
  • Server connected through high-speed telephone lines, fiber optic links or satellite
  • Providing high speed data transfer
  • Connected to bank of modems
  • User modem dials up ISP’s modem and make a connection DIAL UP CONNECTION

FTP Software/downloading a file using FTP

IDSN Lines

  • Permanent phone line connection to an ISP
  • Transfer data faster
  • Come in a variety of bandwidths (data carrying capacity)

Web Server??? Own ISP

  • Larger organizations
  • Large network of computers and require high internet access

Acceptable use policy

Choosing an ISP

  • Cost: prepaid/rate/joining fee
  • Speed: speed of modem supports/support lines for IDSN/cable modems
  • Lines: Line per customer
  • Start up Help: software provided- min. email program/borwser
  • Ongoing support
  • Experience
  • Platform: IBM Vs Macintosh Vs Windows version
  • Accounts: cheque?
  • Newsgroups: Limit to number can join?
  • Additional Mail Boxes e.g. AOL
  • Web Page: Space on server? Size?

What is WWW?

  • World Wide Web
  • Portion of internet containing websites
  • Information can be accessed electronically
  • Collection of hyperlinked documents accessible on the internet
  • Hyperlinks allow you to move quickly from one document to another
  • Web contains millions of documents known as Web Pages
  • Held on various computer networks around the world

How a modem works

Packets

  • Internet operates by dividing data in into separate parts –“packets”
  • And sending these packets along best route available to destination of computer
  • Information is then reassembled into original message
  • Breaking a message into individual packets “packet switching”
  • Software used for packet switching is a communications protocol TCP/IP (Transmission control protocol/Internet protocol)

Firewall

  • Both hardware and software used to restrict access to data on a network
  • Used to deny access to outsiders and restrict employee’s access to sensitive data

Implementation

  • Place a computer “proxy server” between two separate networks
  • Programmed to allow access to/from only specific network locations

File Compression/Decompression Software

  • Reduce download time
  • Internet is used to transfer files
  • File Transfer Protocol (FTP) – standard “language” used by computers
  • Allowing one program to transfer data to another e.g. Archie, Fetch, Most Web Browsers
  • Decompression program needed for ‘expansion’

Search Engine (search tool)

  • Software program searches documents for specified keywords and returns a list of documents where the keywords
  • Matches 1+ keywords answered
  • Searches an index of Internet sites, which is always updated

Function

  • Send out automated ‘spiders’ ‘crawlers’ ‘robots’ to scour internet
  • Search engine sends out ‘spider’ to fetch as many documents as possible
  • Program: ‘indexer’ reads documents and creates an index based on words

1)User types in word/phrase

2)Matched against database

3)Search engine displays URL matching

Newsgroup

  • Collection of news and discussion groups accessed via the internet to a central location
  • Allows anyone to read/post messages on particular topic
  • Divided into groups and subgroups
  • Participation requires program called “newsreader”

Mailing List

  • List of email addresses identified by a single name
  • Messages are distributed to a large number of people via email
  • Join = subscribe
  • Get off mailing List = unsubscribe
  • Lurking: on mailing list without posting messages  explore
  • Flaming:email of personal nature resulting in disagreements among members – don’t reply/inflame
  • Emotions

Search Engine Vs FTP Vs Archie Server

  • Search engine: Generally used to locate information
  • Archie: program that enables you to search for files anywhere on the internet by filename
  • FTP sites are searchable with Archie

Plug-in

  • Mini applications that add extra functions to web browsers
  • E.g. allows recognition/play audio/video files

Browser

  • Software file that allows you to view HTML files
  • Interprets and displays Web pages and enables you to link to other Web pages
  • Basic Function: interpret Hyper Text Markup Language
  • Modern browsers e.g. MS Windows Explorer/Netscape
  • Display/deal with Graphics
  • Play sounds & video
  • Transfer files

Protocols

HTTP

  • Hyper Text Mark Up Language
  • Set of special instructions used to create Web Pages
  • Special instructions called ‘tags’ or ‘markups’ that specify links to other documents and how page is displayed

TCP/IP

  • Transmission control protocol/Internet Protocol
  • Communications protocol used to packet switching on internet

FTP

  • File transfer protocol
  • Internet standard that allows the exchange of files with other computers on the Internet

PPP

  • Point to Point Protocol
  • Version of internet communications protocol TCP/IP widely used by ISP

Cookie

  • Web server that stores on your computer when you visit a site
  • Used to record your viewing preferences
  • Read by website that placed cookie
  • Purpose: identify users and possibly prepare customized web pages for them

Header of Email:

  • Electronic exchange of messages to and from other computer users

1)Date

2)Subject: useful for recipient

3)To: (recipient) must be typed correctly

4)From

5)Reply

6)Reply all

7)Cc - “carbon copy” (duplication)

8)Bcc – “blind carbon copy” recipient not aware of who else received copy

Requirements of email

  • Computer linked to internet via LAN/modem
  • Account – ISP
  • Email address (provided by ISP)
  • Email Software

Communications software

URL

  • Uniform Resource Locator
  • Address that points to a specific resource on the Internet
  • Always written in lower case

Email

  • Allows people to communicate by sending/receiving electronic messages via computers linked to the Internet
  • Letter written & sent  ISP  Routed through various gateways & hosts  satellite link  Routed though various hosts & gateways  ISP  Mailbox opened with password & letter received
  • Economical, fats, convenient
  • EMAILS CAN SEND/RECEIVE FILES – ATTACTHMENTS

Requirements for Email

  • Computer linked to Internet via LAN/modem & telephone line
  • ISP
  • Email address
  • Email software

Email addresses

  • @----- domain name – location of person’s account on Internet ‘com’ commercial
  • Often informal, short, to the point, abbreviations e.g. thanx,

Email Software

1)Stand alone email programs

  • E.g. MS Outlook

2) Mail ‘modules’ of larger Web Browser Packages

  • MS Internet Mail components of Web Browsers
  • Perform similar programs: send/receive/manage email
  • Usually for different platforms

Sending & Receiving email

  • Not necessary to be online when composing
  1. sender connects to internet
  2. sends email
  3. email software connects to ISP mail server & sends the message
  4. mail server sends message
  5. recipient’s mail server puts the message in the recipient’s mailbox. There are two main types 1) POP (Post Office Protocol) or IMAP (Interactive Mail Access Protocol)
  6. Recipient’s email software alerts them that they have received a message
  7. sender’s email software generally save s a copy of message onto hard disk

Replying to an email

  • software creates a new message which is already addressed and includes a copy of the contents of original message
  • subject line automatically filled out “Re:”

‘Bounced’ Messages

  • recipient’s email address may have been mistyped
  • recipient may have changed their email address
  • problem on the Internet

ATTACHEMNTS

  • Anything that can be saved onto a file co be sent as an attachment
  • First must be ‘encoded’ : e.g. email program use MIME (multi purpose Internet Mail extensions)
  • Internet protocol that is able to negotiate many different operating systems & types of software to enable file attachments
  • Recipient must also have same software used to create attachment/converter
  • Large files should be compressed using utility software
  • Bandwidths: info. carrying capacity of cables, wires, modems that connect comp. together
  • Puts limit on amount of data that can be carried at a time

Bookmark

  • Title and URL of a Web page, recorded in the browser so user can return to the Web Page, recorded in a future session
  • Adding:
  • Managing:

HTML

  • Hyper Text Mark Up language
  • Set of special instructions used to create web pages

Privacy/Security: Internet

IP

  • Internet protocol
  • Addressing system for the Internet
  • Consist of four part numeric addresses, identifying the geographic region, company, computer group, and the specific computer location

Netiquette

  • Guidelines developed for posting articles to newsgroups/email
  • Don’t type in capitals
  • Treat people as if in real life
  • Proofread offline
  • Identify subject ie. Posting
  • Make sure message appropriate to list / no personal/ unsubscribe in public domain

TCP/IP

  • Transmission Control Protocol/Internet Protocol
  • Communications protocol used for packet switching on the Internet

Creating a Web Page

  • Analyze
  • Purpose/Achieve/Audience
  • Important info legible?
  • Too many pictures/animations
  • Which web browsers does page support
  • Contacts/Feedback?
  • Design
  • Layout
  • Appropriate user interface with simple navigation tools
  • Home Page interesting to grab user’s attention
  • Implement

Software

  • Web Editor/Web Authoring package: enables you to create Web Pages
  • Technically any software letting you save HTML format e.g. Word processing can be used – compatibility of MS Word Vs Macintosh upon upload

Types

1)Text Based editors: help you create HTML files by inserting HTML codes that help you manage links

  • Requires some knowledge of HTML

2) WYSIWYG editors: work with visual representation of web page

  • Hides HTML code unless you want to see it
  • Import Clips like desktop publishing e.g. MS FrontPage

Text

  • Written in word processing package for proofread/spell-check
  • Fonts used will be stored on viewers computer  use common font

Graphics

  • KISS – slows time
  • Ensure people who choose to turn off “auto load” can still navigate
  • No discrimination for e.g. visually impaired

Icons/Symbols

  • Navigation aids

Sound/Video

  • Limits on modem i.e. bandwidths (data capacity)
  • Employ streaming : Delivered in small packets at regular intervals  sufficient  poor quality
  • Obtain permission
  • Don’t make essential (i.e. those lacking hardware)

Copyright

  • Acknowledgment
  • Permission

Upload

Maintain

Advertise

  • Join major search engine ‘add a page’

Evaluate

  • Independently – someone else
  • Efficiency
  • Effectiveness
  • Navigation/cost/download/ISP size allowance