IPv6 (Internet Protocol version 6) is the next generation of IP addressing, designed to overcome the limitations of IPv4 and address the growing need for more available addresses. IPv6 introduces a new addressing scheme, providing a significantly larger address space and improved functionality. This article provides an overview of the basics of IPv6 addressing and subnetting, including an example format of an IPv6 address.

IPv6 Address Format:

An IPv6 address is a 128-bit binary number, represented in a human-readable format using hexadecimal digits and colons. The 128 bits are divided into eight 16-bit blocks, separated by colons. Each block is represented by four hexadecimal digits. For example, an IPv6 address might appear as:


However, IPv6 addresses can be simplified by removing leading zeros and consecutive blocks of zeros, represented by double colons (::). The simplified form of the above address would be:


IPv6 Address Types:

IPv6 introduces different types of addresses to serve various purposes. The commonly used types are:

  1. Unicast Address: Identifies a single interface on a network. It can be globally unique, link-local, or site-local.
  2. Multicast Address: Identifies a group of interfaces on multiple networks. It allows for efficient distribution of data to multiple recipients simultaneously.
  3. Anycast Address: Represents a group of interfaces, but the packet is delivered to the nearest interface in the group based on routing protocols.

IPv6 Subnetting:

IPv6 subnetting is the process of dividing an IPv6 network into smaller subnetworks, or subnets, to efficiently allocate addresses and manage network resources. Subnetting allows organizations to organize their networks, control network traffic, and optimize address utilization.

In IPv6, the subnetting process is similar to IPv4, but with some differences in the subnet prefix length. The subnet prefix is represented by a value that indicates the number of bits used for the network prefix. For example, a /64 subnet prefix length means that the first 64 bits of the IPv6 address are used to identify the network, and the remaining bits are used for device addressing.

Example IPv6 Address:

Let’s consider an example of an IPv6 address and subnetting:

IPv6 Address: 2001:0db8:85a3:0000:0000:8a2e:0370:7334

Subnet Prefix: /64

Subnetting allows us to divide the network into smaller subnets, each with its own unique network identifier. For instance, we can subnet the above network into four subnets:

  1. Subnet 1: 2001:0db8:85a3::/64
  2. Subnet 2: 2001:0db8:85a3:1::/64
  3. Subnet 3: 2001:0db8:85a3:2::/64
  4. Subnet 4: 2001:0db8:85a3:3::/64

In this example, the first 64 bits represent the network portion, while the remaining bits are available for host addressing within each subnet.


IPv6 introduces a new addressing scheme with a larger address space, providing improved functionality for addressing and subnetting compared to IPv4. The IPv6 address format consists of eight 16-bit blocks represented by hexadecimal digits. Subnetting in IPv6 allows for efficient allocation of addresses and management of network resources. By understanding the basics of IPv6 addressing and subnetting, organizations can effectively design and manage their networks to meet the evolving demands of the Internet.