Countermeasures

They are policies and procedures that are used to safeguard the organization from attacks and potential threats. It is an action, steps, process, or a device that helps to mitigate threats or the effects of the threats. It does so by either reducing the weakness of the network or by reducing the threat. Countermeasures can be taken in the form of software or hardware. For example, a machine has been un-patched and the machine is highly vulnerable. If that machine is unplugged from the network and ceases to exchange data with any other device, you have successfully saved your network from vulnerabilities.  

After identifying assets and considering the risks involved in securing the asset from threats and attacks, the organization should plan to implement countermeasures to protect any threats and minimize any risks of data loss or theft. These countermeasures can be classified the following types:

• Administrative: These are policies, procedures, guidelines, and standards. For example, an Acceptable Use Policy (AUP) is a policy that is agreed to by all the users in the network. 
• Physical: Physical security controls prevent unauthorized users from accessing a secure location. For example, using a rack for the servers and wiring closets on the floor. Another example is using redundant power supplies for a system.
• Logical: This type of control includes passwords, firewalls, intrusion prevention systems, access lists, and VPNs. These are defined in software as opposed to the physical control, such as a physical lock on a door.