The counter-proposal to IPv6's 128-bits was 64-bits. This is 16 quintillion devices, which seems fine.
Doubling the address space is a good strategy when you need more. Quadrupling it is over-engineering.
Doubling the address space is a good strategy when you need more. Quadrupling it is over-engineering.
64 bits are already a pain in the ass to remember, and if you have specific memorization needs you can use small static IPs so that even with 128 bits available you only use about 64 of them.
New L3 protocols on the Internet are firmly on the "incredibly difficult and time consuming" side.