NSS-ICT‎ > ‎Unit C‎ > ‎

Chapter 18

Internet Services and Applications

18.1 Information search on the Internet

A search engine composed of
- a spider (a bot) search through out the Internet. In the web page you write, you can add some code to indicate that you do not want to be INDEXED.
- catalogues and stores the information into a huge database
- a program to access search requests and returns search result.

In writing web pages, you can add some code inside your web page, inform the search engine not to index your page. They may still searching your web with spider, but not shown as search result.

Skills of searching
- provide more specific information (P.258-259 of text book)

General search: e.g. http://www.google.com

specific search : e.g. http://scholar.google.com.hk/ search scholarly paper (academic)

18.2 Analysis of information source
Many information on the Internet is unverified, incomplete and unreliable . 

The search result from different search engine site vary greatly.
Try to search '8964' or '佔中' in the following search engine
Censorship in China

Especially in social media, please don't forward unverified information. A lot of message forward recently are found to be fake.

- information is neutral?
- background of organization.
- Reputation of organization. (non-profit)

18.3 Internet Services

Refer to text book chapter 18 and (multimedia)
Refer to discussion in Chapter 17

 ServicesProtocol  Remarks
 World Wide WebHTTP Different Multimedia element increase the bandwidth requirement.
Develop high compression ratio file type.
Plugin: different media player
 File TransferFTP 
FTP:NOT Encrypted 
SSH FTP: Encrypted
SMTP: sent mail
POP/IMAP: retrieve mail
advantage of email, spam problem etc 
 Newsgroup Use software to read and post message
Features: Similar to discussion forum 
 Discussion forum  
 Online Chat  
 Remote logon Telnet
Telnet: No encryption
SSH : with encryption
Remote Desktop in windows: 
StreamingStreaming: Play before complete download
Webcast: MMS, RTSP  
YouTube http://www.youtube.com,  RTHK http://www.rthk.hk
 Voice Over IP  Skype
 Voice mail Yahoo! messenger 
 Video conference For high quality video conference, it needs high and stable bandwidth.
Leased line may be used. It can be rent by hour. 

18.4 Streaming technology on the Internet
Compression ration is high.

18.5 e-commerce
e-commerce covers business activities on the Internet
e-commerce model
- B2B  (Business to Business) 
   Largest B2B platform in China: http://www.alibaba.com)
- B2C  (Business to Consumer)
    http://www.cxholidays.com  (Travel package)
    http://www.parknshop.com  (Supermarket)
    http://www.bochk.com (Banking)
- C2C  (Consumer to Consumer)
   usually buy and sell items through an auction process  ebay or yahoo!Auction

transaction must be encrypted.

Components in B2C e-commerce
- Categories of products
- Shopping Cart, usually stores as cookies in your computer.
- Electronic payment: Credit card, paypal etc.

Electronic payment:
- 2 factors of authentication.
     - possession factor - thing you own (security device)
     - knowledge factor - things you know (password)
    - inherent factor (e.g. bio-metric measure)
Payment method
- third party payment platform. (Paypal, Octopus ...)
Lots of new payment method.

Advantages and disadvantages for e-commerce (refer to p.289)

18.6 e-government
- pay government bills
- book public facilities or appointment
- reserve, renew return date of books,  read e-books in library (http://www.hkpl.gov.hk)

One stop portal

Advantage and limitation of using e-government (P.293)

18.7 e-learning

e-learning: learn by using computer, mobile device (Tablets/ mobile phone), Internet, e-mails, discussion forum and other learning software.

web based learning:
- content delivery (lecture notes, video etc)
- content developing system
- network community of learners. (Discussion forum, peer assessment via Internet)

Features of e-learning (P.294)

Impacts on teaching and learning.

MOOC (Massive Open Online course) http://www.coursera.org 
   Identify the features of the platform.

Platform for e-learning 
   Paid platform: eclassrooom in eclass
   Open sources platform: Moodle, you have to install a server. e.g. http://comp.rhs.edu.hk/moodle/
   Web based platform: Google Classroom, Edmodo (https://rhss.edmodo.com)

18.8 Online entertainment

Online Game
- may free for installation, needs to spend money in progress.
- connected with social media.

Online informative entertainment

Web site or mobile apps

Internet TV (e.g. HKTV)
Internet Radio (e.g. rthk) 
Music Web site
Film web site (watching movie via web or mobile apps)
Newspaper web site and online magazine. 

Live Broadcast / Webcast: One to Many. The packets from the server sent to many user.

Video conference between multiple location: Many to Many

Social media also help distributing news.
Lower set up cost for an online newspaper.
customize news feeding. 

Benefits and limitation (P.297)
- may not censored. It can be an advantage and disadvantage.
TVB are famous of self censorship in recent student demonstration news.
Internet provides lots of information about the demonstration or from your friends.

Internet addiction disorder - Addiction to Internet and online games.

18.9 Impacts of ICT on the society.
Information flow is fast - the age of big data. 
Monitoring of human activities. lack of privacy.
Lot of new services in Internet
IT Infrastructure needed to be protect.

Subpages (1): Google Account