What Is IPv6?

Why Use IPv6 vs IPv4?

The primary reason to make the change is due to IPv6 addressing. IPv4 is based on 32-bit addressing, limiting it to a total of 4.3 billion addresses. IPv6 is based on 128-bit addressing and can support 340 undecillion, which is 340 trillion³ addresses. Having more addresses has grown in importance with the expansion of smart devices and connectivity. IPv6 provides more than enough globally unique IP addresses for every networked device currently on the planet, helping ensure providers can keep pace with the expected proliferation of IP-based devices.

In addition to addressing, IPv6 benefits include:

• Stateless address autoconfiguration
• Optional NAT (Network Address Translation)
• Easier administration with DHCPv6
• Improved quality of service with flow labeling

IPv6 addressing structure

IPv6 uses hexadecimal digits (hex digit) for addressing with each hex digit representing 4 bits.

IPv6 addressing can reduce routing table size by allowing ISPs to aggregate customers' prefixes into a single prefix and present only that one prefix out to the IPv6 internet.

Many networks will implement IPv6 concurrently with IPv4 in a dual-stack design, while newer networks will deploy IPv6 natively but still allow for compatibility with IPv4 if needed. This addresses current government mandates for IPv6 use.