During a press conference at the Heidelberg Laureate Forum in Germany, Cerf said that he would have put in a 128-bit address space so we wouldn’t have to go through this painful, 20-year process of going from IPv4 to IPv6.
IPv4, the first publicly used version of the Internet Protocol, included an addressing system that used 32-bit numerical identifiers which rapidly ran out of addresses.
Cerf would also have added public key cryptography.
Trouble is, neither idea is likely to have made it into the final result at the time. “I doubt I could have gotten away with either So today we have to retrofit.”
Having a 128-bit address space wouldn’t have seemed realistic back then given the effort’s experimental mind-set at the time.
There was debate about the possibility of variable-length addresses, but proponents of the idea were ultimately defeated because of the extra processing power associated with them, he explained.
As for public key cryptography, the notion had only recently emerged around the time the internet protocols were being standardized back in 1978.
“I didn’t want to go back and retrofit everything, so we didn’t include it. If I could go back and put in public key crypto, I probably would try.