1.4 Moving data around
This part gives a brief introduction to the way data travels around a computer network. It will:
- give you an insight into the layered model of communications networks
- remind you what a protocol is
- introduce you to the TCP/IP protocol suite.
There is one short video and some activities. When you have completed this part you will be able to use the analogy of transporting goods using shipping containers to explain the way data travels round a computer network. In particular you should be able to appreciate the use of a layered model to separate, describe, explain and implement the tasks and processes involved and appreciate the significance of a layered model in communication networks.
Watch the video below, which is about 6 minutes long. It uses the analogy of moving goods around to explain the ideas about moving data across networks.
Activity 8 Think about
What do you think is the benefit of splitting the tasks into a collection of different independent layers?
With each layer being independent of the others, a layer can be changed or amended without affecting the performance of the layers above or below it.
Which layer in the TCP/IP protocol stack do you think is responsible for placing data on the physical medium?
Earlier on I said that the physical medium resides at the bottom layer, so in the TCP/IP protocol stack this is the Network Access layer.