Cat module 2

• LAN

  Network which connects computers in a small area such as a school
• Intranet

  Organisation's private network-internet-like environment consisting of web pages relating to the organisation's business
• Basic components of a network

  • Computers
  • Peripherals
  • NIC
  • Switch
• Clients

  Computing devices that use network resources
• Servers

  Powerful computers that provide resources
• Types of servers

  • File server
  • Email server
  • Internet or proxy server
  • Print server
• Network Interface Controller (NIC)


  Connects computer to a cabled network, allows computer to communicate with the network
• Switch

  Device that connects computers in a network with cables, to enable communication between them (but not used for internet access)
• Wireless Access Points

  • Connected to a cabled network
  • Number determined by size of network (distances between buildings, etc.)
• Most desktop operating systems have built-in networking capabilities
• Advantages of a LAN

  • Software, hardware and internet access shared by users
  • Files accessed anywhere on the network, bandwidth easily shared
  • Security and user access controlled from a server
  • Software easily updated from one location
• Disadvantages of a LAN

  • Can be expensive to install and maintain
  • A network administrator is necessary
  • Network security must be maintained
  • If the server is faulty, nobody can access their files
• Potential disadvantages of a WAN

  • Less secure than using cables
  • Poorer network performance (as more computers are added)
  • Signal loss due to electronic or electrical interference
• Password best practices

  • Change password every 2 months or so
  • Avoid using same password for any two sites
  • At least 8 characters long
  • Mixture of upper and lowercase letters, numbers and special characters
  • Avoid using anything that is easy to guess about you
  • Avoid keyboard patterns like asdf and '1234'
• Acceptable Use Policy (AUP)

  • Outlines rights and responsibilities of network users
  • Includes promotion of basic netiquette rules and importance of sticking to ethical, legal and safe practices
  • Includes restrictions on what may be accessed online, amount of data downloaded, use of portable storage devices, installing hardware/software
  • Includes procedures to follow if users are victims of identity theft, malware, cyber-bullying, etc.
  • Includes consequences of violating AUP conditions
• Readability and usability of websites is important
• Factors that improve website readability and usability

  • Headings, short paragraphs and columns
  • Numbered or bulleted lists, and keeping text short and to the point
  • Grouping related ideas in a logical order
  • Appropriate type, size and colour of fonts
  • Avoiding text all in upper case
  • Page backgrounds that are easy on the eye
• Navigation

  • The menu system should be easy to locate and identify
  • Links: short and descriptive, no "broken links", formatted in a consistent way
• Consistency

  Consistent design and layout makes the structure of a site easier to understand, to navigate and to read - same basic layout, same colours and fonts
• Layout refers to how the various elements of a web page are arranged
• Page contents should fit standard monitor sizes and resolutions
• Typography

  The suitable placing and formatting of text, using fonts that are easy to read and match their content, commonly-used fonts that are likely to be on the user's system, not too many different types
• Other factors that affect the browsing experience

  • Speed - Pages should be designed to load quickly
  • Privacy - What you do on the web is not always 'private'!
  • Spyware - Any technique or software that tries to monitor and track the way you use your computer, and then report this information to a third party
  • Adware - Free software that is ad-sponsored and pops up adverts while the program is running
• Internet access options

  • Fixed internet access (ADSL, fibre)
  • Mobile internet access (WiFi, WiMAX, 3G, 4G)
• WiFi

  A wireless networking technology using radio waves to provide internet access and network access between computers and other devices such as smartphones and tablets
• WiMAX

  An upgrade on WiFi and a more secure wireless networking technology that allows wireless devices to communicate with one another over a wider area than WiFi
• 3G and 4G (LTE)

  Generations of mobile (cellular) phone technology
• Hotspot

  A place where a WiFi network has been created so that people can connect to the network- and through it, connect to the internet
• Advantages of social networking sites

  • Cost-effective
  • Can show your 'status' to friends
  • Not bound by geographical differences
  • Marketing tool
• Disadvantages of social networking sites

  • Identity theft and online fraud are risks
  • False information can be posted
  • Loss in productivity
  • Targeted advertising
• Best practices for social networking

  • Check privacy settings
  • Don't post personal information
  • Only accept people you know as friends
  • Don't post inappropriate content
  • Restrict the time you spend on sites
• VoIP

  • Technology that allows telephone calls to be made over LANs, WANs and the internet
  • Generally cheaper than normal phone calls, some are generally free, files can be shared, video conference calls can be made
• Disadvantages of VoIP

  • Call quality on slow internet connections can be poor
  • Can use a lot of data
• Best practices for VoIP

  • Check time zones and contact's status
  • Cut down on the use of video
  • Invest in a decent headset and microphone
• Video conferencing

  Allows two or more people to hold online conferences at different locations
• Advantages of video conferencing

  • You can see the people you are communicating with
  • A call is cheaper than travel costs to the location
• Disadvantages of video conferencing

  • Call quality on slow internet connections can be poor
  • Can use a lot of data
• Best practices for video conferencing

  • Use a well-located setup
  • Check sound and video quality before the call
  • Check the privacy of your surroundings
• Chat rooms/applications

  Any online environment that allows people to 'chat' in real time
• Advantages of chat rooms/applications

  • Ability to chat with more than one person at a time
  • Interact with people regardless of geographical location
  • Applications can be used on a variety of platforms