Multimedia Internet Communications - Lecture 41 CP2022 INTERNET and World Wide Web

Multimedia Internet Communications - Lecture 42 A simple view of the Internet A network of networks World-wide inter-linked computers…

Multimedia Internet Communications - Lecture 43 What is the Internet ? Large collection of connected computers across the world Linked networks and networks within networks…… Began in 1970s - mainly US-based academic, military and research networks Used mainly for research and knowledge sharing purposes One aim was to establish a facility to enable communication even in the event of a nuclear attack

Multimedia Internet Communications - Lecture 44 Evolution of the Internet Internet = , file transfer, newsgroups, and hypertext transfer (WWW) Over recent years the size and scope of the Internet network(s) have almost ‘exploded’ World-wide group of users of millions …. And still growing Redesign/restructuring is an issue - to cope with this phenomenal growth and the increasing use of multimedia.

Multimedia Internet Communications - Lecture 45 What Services are Offered ? The World Wide Web based on the hyper-text transfer protocol (http) Millions of sites for a range of subjects/interests File transfer Discusssion forums, instant messaging, online services (e.g. library renewals) Streaming multimedia

Multimedia Internet Communications - Lecture advantages Speed ( especially long distance ) Reduction in paperwork (for memos) Messages/documents transmitted + received when convenient Permanent record of dialogue Direct access can be a ‘social leveller’

Multimedia Internet Communications - Lecture disadvantages Junk mail /Spam Face - face dialogue has the edge Systems fail! Delays in receipt can be unpredictable and excessive Access constraints (to hardware) can be limiting

Multimedia Internet Communications - Lecture 48 How do you access the World- Wide Web? Uses a computer program called a browser Microsoft Internet Explorer Netscape navigator Others Give the name of the computer you want to access and the location of the file ! (URL) e.g Or use the mouse to click on links Or use bookmarks to return to frequently visited sites

Multimedia Internet Communications - Lecture 49 What is on the Web ? Academic Publications and Research/reference information Non-academic information (e.g. on football teams, celebrities etc.) Services such as shopping, buying books and software, renewing library books, etc. Scope of use is widening - video broadcasting, remote directed surgery, interactive entertainment, etc.

Multimedia Internet Communications - Lecture 410 How do you find useful information? There are millions of documents on the web to search through ! Luckily there are tools to help. Try using a Search ‘Engine’. For example, Google, Alta Vista, An example web page:-

Multimedia Internet Communications - Lecture 411 Internet communication TCP/IP is used to communicate packets of information between users and other parts/users of the Internet. Permanent connections High data rate links at universities Broadband connections Dial-up access via telephone/ISDN lines Individuals can access through ISPs (Internet service providers) or other establishments (e.g.university)

Multimedia Internet Communications - Lecture 412 Some predictions (1998) A U.S. survey predicted by 2002: PCs = net access in 47 m homes TV based = 12.7 m homes Screen phones = 2.6m homes Now - 250m Internet users in the North America PC-centric Net and TV-centric Net (web-TV) ‘intelligent’ software used on shopping web sites keeps track of users’ preferences and interests leads to ability to suggest products etc.

Multimedia Internet Communications - Lecture 413 Internet usage in the EU

Multimedia Internet Communications - Lecture 414 More snippets ….. Trend for commercial web sites to look for ‘value added’ content to attract and retain interest (discussion forums) Fastest growing groups of web users - under 18s and over 55s Average web users surfs for 1-2 hours/day

Multimedia Internet Communications - Lecture 415 And more snippets …. Users’ online time (survey):- Entertainment sites = 14% Education = 1% Communications 1/4% 84% regularly use 40% visit chat rooms/discussion forums Internet2 - the ‘next generation’ internet will be up to 1,000 times faster (over next few years)

Multimedia Internet Communications - Lecture 416 Summary The Internet is now a primary means of communication It isn’t designed for multimedia Now difficult to work without Web browsing is both work and leisure activity The Internet is being developed for greater speed and better access to information