In the prvious section, you learned that networks are susceptible to hackers and unauthorized access. As a result, organizations need to control access to the resources on a network. Most distributed netwroks supports multiple users, each with different access permissions to the resources and computers on the networks the informations and assets in an organization are crucial and keeping them safe constitues network security. The security model of a network should ensure

control on resources by using the following mechanisms :

• Authenctication
  

• Access Control
  

• Data encryption
  

• Auditing
  

• Intrusion detection
  

• Securing servers