15.2 Objectives and Threats

The objectives of networks and communication security are as follows:

Prevention of the release of message content (either through copper cables, fibre optic or wireless networks).

Eavesdropping – Eavesdropping is the act of listening in to other’s conversations.

			This is also present in computer networks as eavesdroppers (hackers) listen into conversations (data being sent) between one computer to another in a network.
			This can be through the use of sniffers if it is a wireless network or through the electro-magnetic transmissions that are outputted by the copper cables connecting the computers.
			This phenomenon is also known as wiretapping.

Prevention of traffic analysis – Traffic/data analysis between computers occurs when data or information is not encrypted (or is not fully encrypted) and transmitted across a network.

Traffic analysis is used to examine the data to determine the patterns of communication being exchanged.

Link encryption solves this threat as it encrypts the data as well as the data header, unlike end to end encryption.

Detection of denial of service attempts – Denial of service attacks generally manage to enter a system or a network and overload it with information causing it to slow down and in some cases, stop functioning all together.

This prevents communication across the network as all communication can come to a halt.