When to Use Private IPv4 Addresses

BD

Private IPv4 addresses are non-routable IP addresses that are used within a private network. They are designed to be used by organizations to allow internal communication within the network without having to use public IP addresses. Here are the two circumstances where private IPv4 addresses are appropriate:

1. On hosts that communicate only with other internal hosts: Private IPv4 addresses are suitable for internal hosts that communicate only with other internal hosts. For instance, if an organization has multiple departments or branches, each department can be assigned a private IP address range that is only used within the department. By doing so, the organization can avoid using public IP addresses and conserve them for other external purposes.

2. On hosts that require minimal access to external resources: If hosts within an organization require only minimal access to external resources, private IP addresses can be used. This is because private IP addresses cannot be used on the public internet and are only accessible within a private network. Therefore, using private IP addresses can provide an extra layer of security for hosts that require minimal external access.

In contrast, public IP addresses are used for hosts that require access to the internet or external resources. For example, public IP addresses are used for servers that provide web services or for computers that need to access external resources such as websites or cloud services.

Hence, options B and D are the correct answers.