IPv6 is the latest version of Internet Protocol. It is intended to replace IPv4. v6 uses a 128-bit address, allowing 2^128, or approximately 3.4×1038 addresses, or more than 7.9×1028 times as many as IPv4, which uses 32-bit addresses. IPv4 allows only approximately 4.3 billion addresses.
IPv6 addresses are represented as eight groups of four hexadecimal digits separated by colons, for example 2405:8a00:1000:A:B:200:100:1.
NKN core has been migrated to IPv6 and running the dual-stack in edge network. NKN has got a 2405:8A00::/32 IPv6 block from APNIC (RIR for asia pacific region) and allocating /48 ipv6 address block to its member connected institutes at free of cost.
If you still didn't get your IPv6 block from NKN, ask immediately for the same.
In case of any doubt, pl. drop a mail to support@nkn.in OR v6@nkn.in