Networking - 1.0 - The communications

The Elements of Communication

Communication begins with a message, or information, that must be sent from one individual or device to another using many different communication methods.

All of these methods have 3 elements in common:

  • Message source or sender
  • Destination or receiver
  • Channel

Communicating the Messages

Data is divided into smaller parts during transmission ➔ Segmentation

The benefits of doing so:

  • Many different conversations can be interleaved on the network. The process used to interleave the pieces of separate conversations together on the network is called multiplexing.

  • Increase the reliability of network communications. The separate pieces of each message need not travel the same pathway across the network from source to destination

  • Downside of segmentation and multiplexing

  • Level of complexity is added (process of addressing, labeling, sending, receiving and etc are time consuming)

  • Each segment of the message must go through a similar process to ensure that it gets to the correct destination and can be reassembled into the content of the original message

  • Various types of devices throughout the network participate in ensuring that the pieces of the message arrive reliably at their destination

Sample network diagram

Components of the Network

  • Devices (PCs, intermediary devices)
  • Media (Cable or wireless)
  • Services and processes (Software)

End Devices and Their Roles

In the context of a network, end devices are referred to as hosts.

A host device is either the sender or receiver

To distinguish one host from another, each host on a network is identified by an address.

Software determines the role of a host. A host can be a client, server or both


  • Computers, workstations, laptops, and servers…..
  • Network printers
  • Voice over Internet Protocol (VoIP) phones
  • Handheld devices like PDA, mobile phones…
  • Cameras on a network, webcams and security cameras