Question

What is the recommended prefix length for most IPv6 subnets?

A. /32
B. /48
C. /64
D. /128

Answer 1

The recommended prefix length for most IPv6 subnets is 64. Thus (option c) is right answer.

The recommended prefix length for most IPv6 subnets is /64, providing plenty of addresses for devices and supporting features like SLAAC.

Step-by-step explanation:

The recommended prefix length for most IPv6 subnets is /64. Thus (option c) is right answer.

This recommendation comes from the Internet Engineering Task Force (IETF) in order to facilitate address autoconfiguration and subnetting practices. With a /64 subnet, there are 264 or approximately 18.4 quintillion possible unique addresses within each subnet, providing ample space for network devices and services.

Additionally, the /64 boundary aligns with various IPv6 features such as Stateless Address Autoconfiguration (SLAAC) and aids in optimal network organization and future growth.

Answer 2

The recommended prefix length for most IPv6 subnets is /64. It balances the need for a vast number of addresses with the simplicity of network management, and is required for features like SLAAC.

Step-by-step explanation:

The recommended prefix length for most IPv6 subnets is /64. This allocation allows for a significant amount of uniquely addressable devices within a single subnet. Each IPv6 address is made up of 128 bits. Dividing the address space into a 64-bit network portion and a 64-bit host portion simplifies address assignment and subnetting. A /64 subnet has enough address space to assign 18 quintillion unique IP addresses, which is sufficient for most network scenarios.

Using a /64 prefix length is also important for the proper functioning of certain IPv6 features, such as Stateless Address Autoconfiguration (SLAAC), which requires a /64 subnet to operate. It is worth noting, however, that organizations may use different prefix lengths for aggregating multiple subnets or for routing purposes, such as /48 for site-level allocations or /56 for smaller site divisions.