Network Security

Connecting computers together creates enormous value, but it also exposes them to attack. Network security is the set of measures used to protect data and resources as they travel across and are stored on a network. Good security aims to preserve three qualities: confidentiality (only authorized people can read the data), integrity (data is not altered without permission), and availability (the network and its services remain usable). This lesson surveys the main threats and the key defenses, including encryption, authentication, firewalls, MAC filtering, trusted networks, and VPNs.

Common threats

Networks face many kinds of threats. Malware such as viruses, worms, and ransomware can spread between connected machines and damage or lock up data. In an eavesdropping or packet-sniffing attack