7.1 Internet Protocols

7.1 Internet Protocols

1. Ethernet

   • Used to operate LAN (Local Area Network)
   • Made up of
     • Data sending/receiving devices (ex: PC, printers)
     • Data packets receiving/forwarding network devices (ex: hubs, switches, routers)
     • Medium connecting device (Twisted pair, fibre optic, coaxial cable)

2. TCP/IP

   • TCP - ensures accurate data transmission
     • Removes duplicates
     • Handshakes another copy if it does not arrive within certain time
     • Connection-oriented service - requires handshaking before data exchange
     • Congestion control - limits speed of data tranfer
       • Reduces congestion and loss of data
       • Lack of speed and delays
         • Unsuitable for real-time application
   • IP - deliver to correct address
   • Every device on network has an IP address
     • Consists of 4 bytes of data
       • Byte - eight binary digits/bits
   • Data divided into packets (with destination and source IP addresses)

3. Handshaking

   • Allow communication - recognise and agree
   • Parity check - verifying data has been transmitted accurately
     • Protocol which makes the bytes of data even - adds an additional byte (0/1)

4. UDP

   • Connectionless service - no handshaking required
   • Just send data packets

5. FTP

   • One layer above

6. HTTP

7. Telnet

8. SSH

9. Protocol Layers

   • 1 Physical
     • Data transmitted bit by bit from device to device
     • Modems
   • 2 Data link
     • Acts upon request for services from network layer and physical layer
     • WiFi
     • Ethernet
   • 3 Network/Internet
     • responsible for:   -forwarding packets   -routing   -dealing with TCP/IP protocols
     • Internet protocol (IP)
   • 4 Transport
     •   -Responsible for dividing transmitting data into smaller packets   -Adds address of source and destination
     • Transmission control protocol (TCP)
     • User datagram protocol (UDP)
   • 5 Application
     • Consists of protocols that use transport layer to deliver services to network layer
     • File transfer protocol (FTP)
     • Hypertext transfer protocol (HTTP)
     • Telecommunication network (Telnet)
     • Secure shell (SSH)