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What Vint Cerf Would Do Differently (computerworld.com)

An anonymous Slashdot reader quotes ComputerWorld: Vint Cerf is considered a father of the internet, but that doesn't mean there aren't things he would do differently if given a fresh chance to create it all over again. "If I could have justified it, putting in a 128-bit address space would have been nice so we wouldn't have to go through this painful, 20-year process of going from IPv4 to IPv6," Cerf told an audience of journalists Thursday... For security, public key cryptography is another thing Cerf would like to have added, had it been feasible.

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 one," said Cerf, who won a Turing Award in 2004 and is now vice president and chief internet evangelist at Google. "So today we have to retrofit... If I could go back and put in public key crypto, I probably would try."

Vint Cerf answered questions from Slashdot users back in 2011.

1 of 125 comments (clear)

  1. Re:IoA by JesseMcDonald · · Score: 3, Informative

    That would be well and fine if most IPv6 addresses didn't have a 64-bit or even 80-bit prefix, identical for everything routable at the endpoint.

    That 64-bit network prefix is the equivalent of 4 billion entire IPv4 internets—and each "host" in each of those internets contains its very own set of 2**32 IPv4 internets in the 64-bit suffix. Quadrupling the number of bits from 32 to 128 means raising the number of addresses to the fourth power (2**32 vs. 2**128 = (2**32)**4). We can afford to spare a few bits for the sake of a more hierarchical and yet automated allocation policy that addresses some of the more glaring issues with IPv4, like the address conflicts which inevitably occur when merging two existing private networks.

    Think of it this way: If we manage to be just half as efficient in our use of address bits compared to IPv4, it will still be enough to give every public IPv4 address its own private 32-bit IPv4 internet. Right now the vast majority of IPv6 unicast space is still classified as "reserved", so we have plenty of time to adjust our policies if it turns out that we need to be more frugal.

    Then there are DHCP addressing schemes that use the MAC as part of the address, further reducing it.

    Automatic address assignment (based on MAC or random addresses or whatever) comes out of the host-specific suffix, not the network prefix, so it doesn't reduce the number of usable addresses any more than the prefix alone. It does imply that you need at least a 64-bit host part in order to ensure globally uniqueness without manual assignment, but the recommended 64-bit split between network and host was already part of the standard.

    --
    "The state is that great fiction by which everyone tries to live at the expense of everyone else." - Bastiat