Layer 1 – the physical layer

The physical transmission of the data in the form of bits takes place on this layer. Depending on the type of media (see the previous chapter) and the network cards in use, the method of sending the data will vary. The important thing is that both ends are using the same method. These signals may be in the form of variations in voltage or patterns in the light being transmitted. 

At this layer, there are no protocols per second, but there are sets of standards and criteria that the cabling and network cards will need to adhere to. These standards include the following:

  • Voltages
  • Speeds
  • Wiring

With this, we have covered all the seven layers of the OSI network model.

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