Lesson 1.1B: Methods of Computer Communication

• Local Area Network (LAN) - home or office communication of the network.

  • can be either wired (through Ethernet) or wireless (Wi-FI)
• Metropolitan Area Network (MAN) - connection around the city or area.

  • switches/hub
  • routers/bridges
• Wide Area Network (WAN) - can access via the internet around the whole world (different locations).

  • Internet
  • Virtual Private Network
  • Cloud Computing
• NETWORK COMMUNICATION

  ELEMENTS:

  • Message encoding
  • Message formatting and encapsulation
  • Message timing
  • Message size
  • Message delivery options
• Message Encoding - The process of converting data into a format that can be transmitted over a network.

  
• Message Formatting and Encapsulation

  • agreed format
  • encapsulates the information to identify the sender and the receiver lightly
• Message Size - The amount of data that can be sent in a single transmission.

  Must remember that we break long messages into smaller packets to avoid congestion (maximum transmission unit)
• Message Timing

  • Response Timeouts
  • Flow control
  • Synchronization
• Message Delivery Options

  • Unicast - one-to-one communication of data
  • Multicast - if the sender sends the data to set of receivers but not to all
  • Broadcast - sender sends the data to all participants
• Peer-to-Peer Network

  • No Centralized Administration
  • Peer equality
  • Simple sharing applications
  • Not scalable
• Client-Server Network

  • Centralized Administration
  • Request-response model
  • Scalable
  • Server may be overloaded
• SERVICES

  • E-Mail
  • Storage devices
  • File sharing
  • Instant messaging
  • Online game
  • Voice over IP
  • Video Telephony
  • World Wide Web