What is IPv6?
Internet Protocol addresses, or IP addresses, are a core part of how the Internet operates. Every device needs an IP address to connect to the Internet and communicate with other computers, networks and devices. Internet Protocol version 6 (IPv6) is the next generation of the Internet protocol. It was developed to succeed version 4 (IPv4) as IPv4 addresses have almost run out globally. While there are only 3.7 billion unique IPv4 addresses available for use on the Internet, the theoretical IPv6 address pool size is 340 trillion trillion trillion addresses. IPv6 addresses comprise 128 bits and they are usually shown as sequences of hexadecimal digits, separated by a colon character ( : ).
IPv6 example address: 2001:0db8:85a3:0000:0000:8a2e:0370:7334
Benefits What’s the benefit of moving to IPv6? The ability to deploy new services and expand networks without battling constraints of address exhaustion. Speed – many large content providers such as Google, Facebook and LinkedIn have converted their core architecture to preference IPv6. The costs of increasing network complexity associated with IPv4 NAT technology, coupled with rising prices of IPv4 addresses acquired via market transfers can be prohibitive. Studies have shown Total Cost of Ownership of IPv6 is becoming lower. Evidence suggests that the recapitalization of networks can invite new business and help grow market share. IPv6 also offers other technical benefits, including: Increased address space – from 32 bits to 128 bits. Room for many levels of structured hierarchy and routing aggregation. Easier and better address management and delegation than IPv4 (stateless auto-configruation). Dual stack reduces pressure on the CGN and can liberate IPv4 addresses for reuse. IPv6 has lower retained logging costs compared to CGN-based methods where tracking of IP bindings to customers is an issue. Significant deployment of wide-scale devices demands large address pools or concentrations of service behind aggregation points. IPv6 will permit investment in device networks at large scale in simpler models.
Why is it important? Simply put, available IPv4 address space is almost exhausted globally but the demand for addresses continues as the Internet grows. An estimated 40% of the world’s population currently has Internet access, and this is predicted to rise to 52% by 2020. At the same time, the number of devices connected to the Internet will grow massively, as mobile broadband and the Internet of Things become a reality. Estimates range from 26 to 50 billion devices connected to the Internet by 2020. IPv6 offers an enormous number of addresses: a distant future Internet of 100 trillion devices would only consume a mere 5% of the available IPv6 space. It is clear that the only way to support Internet growth in future is through adoption of IPv6, the next generation of IP addresses.
isp_ipv6_address_planning_structure.pdf
https://blog.apnic.net/2018/08/10/how-to-calculating-ipv6-subnets-outside-the-nibble-boundary/