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Lesson 2Security elements
Objective Most important security elements
What are the most important security elements?
Each of the elements of an effective security system operates in conjunction with the others to ensure that an organization can communicate as efficiently as possible.
The MouseOver below is a representation of the most important security elements and of the hierarchy into which these elements are organized.
Security elements
Network Security Test LabNetwork Security

Combining security methods
When planning security, you will use a combination of
  1. methods and
  2. perimeter devices.
To provide access control and authentication, for instance, a system uses some combination of the methods and perimeter devices shown in the table below.


Security Element Perimeter Devices Internal Methods
Authorization and access control 1) Filtering router
2) Firewall
1) Application logic
2) Operating system permissions
Identification and authentication Tokens 1) Remote Access Devices
2) Password Policy
The application of internal methods for security such as auditing and the use of screening routers , firewalls, firewall tokens and remote access devices will be discussed in later modules.
  1. Remote access device: Devices that have access a network from a remote site.
  2. Screening router : Examines inbound and outbound packets based upon filter rules. Screening router is another term for a packet filter.
  3. Firewall: A security system designed to prevent unauthorized access to or from a private network. Firewalls can be implemented in both hardware and software, or a combination of both.
  4. Firewall token: A string of information that identifies a specific user as packets pass through the firewall. A token is usually encrypted.