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

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

Examples:

• 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