Introduction to Industrial Ethernet

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What is data communication

"Data communication deals with the transmission of signals in a reliable and efficient manner."

- Stallings

Ultimately, it's about transmitting data (ie. bits) across a physical transmission medium - such as:

  • Electricity (copper wire)
  • Light - (free space optics, fibre optics)
  • Electromagnetic radiation (WiFi, microwave)

What are computer networks?

"Networking deals with the technology & architecture of the communications networks used to interconnect communication devices."

- Stallings

“… a collection of autonomous computers interconnected by a single techology. The Internet is not a single network but a network of networks.”

- Tanenbaum

Physical device connectivity

Example of a Bus network

Example of a Star network

Example of a Ring network

Example of a Mesh network

 

OSI Seven Layer Model

  • TCP/IP as an example does not accurately map to it
  • Allows designers to split functionality
  • Often referred to (that is a layer 2 switch, that is a layer 3 switch etc.)
  • Most important aspects for us are lowest three layers


OSI Seven Layer Model

OSI Seven Layer Model - Packet example

OSI Packet example