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Vint Cerf Keeps Blaming Himself For IPv4 Limit

netbuzz writes "Everyone knows that IPv4 addresses are nearly gone and the ongoing move to IPv6 is inevitable if not exactly welcomed by all. If you've ever wondered why the IT world finds itself in this situation, Vint Cerf, known far and wide as one of the fathers of the Internet, wants you to know that it's OK to blame him. He certainly does so himself. In fact, he does so time and time and time again."

4 of 309 comments (clear)

  1. an alan cox interview by ciaran_o_riordan · · Score: 5, Informative

    Here's an interview where he says it:

    http://www.velocityreviews.com/forums/t576610-alan-cox-on-software-patents.html

    """Alan Cox: The same has happened with IP version 6. You notice that everyone
    is saying IP version 6 is this, is that, and there's all this research
    software up there. No one at Cisco is releasing big IPv6 routers.
    Not because there's no market demand, but because they want 20
    years to have elapsed from the publication of the standard before
    the product comes out -- because they know that there will be
    hundreds of people who've had guesses at where the standard
    would go and filed patents around it. And it's easier to let things
    lapse for 20 years than fight the system."""

    (More info would be good - any other prominent techs saying this?)

  2. How we got here. by Animats · · Score: 4, Informative

    At the time, XNS, the Xerox protocol for Ethernet networks, was in use. It had 24 bits for the network number, and 24 bits for the device ID. Thinking at the time was that each network would be a local LAN, and "internetworking" would interconnect LANs. Xerox was thinking of this as a business system, with multiple machines on each LAN. So XNS had a 48-bit address spade. That's what we call a "MAC address" today.

    The telephony people were pushing X.25 and TP4, which used phone numbers for addressing. Back then, phone numbers were very hierarchical; the area code and exchange parts of the number determined the routing to the final switch. "Number portability", where all the players have huge tables, was a long way off.

    The problem with a big address space is that memory was too expensive in those days to deal with huge address tables. A big issue was locative vs non-locative address spaces. In a locative address space, there's a hierarchy - you can take some part of the address and make a local decision about what direction to go, even if you don't have enough detailed information to get to the final destination. IP was originally organized like that - routers looked up class A, B, and C networks. A huge, flat address space implemented using multi-level caches was way beyond what you could do in a router back then. Routers used to be dinky machines, with less than one MIPS and maybe 256K of RAM.

    There was a lot of worry about packet overhead. Each key press on a terminal sends 41 bytes over a TCP/IP network. That was a big deal when companies had long-haul links in the 9600 to 56Kb/s range. Adding another 24 bytes to each packet to allow for future expansion seemed grossly excessive. Especially since the X.25 people had far less overhead.

    So there were good reasons not to overdesign the system. I don't blame Cerf for that.

    The foot-dragging on IPv6 is excessive. The big deployment problem was getting it into everyone's Windows desktop. That's been done.

  3. Re:Glad thats sorted out! by hardburn · · Score: 5, Informative

    Except IPv6 is hierarchical, for that very reason. Routing tables can be much, much smaller than they are on IPv4.

    --
    Not a typewriter
  4. Re:Laches: the doctrine of you snooze, you lose by Overzeetop · · Score: 4, Informative

    Never, or in more practical terms, less than 6 years after the expiration of the patent. Patents need not be defended like trademarks, and you can "back sue" for up to 6 years of infringement. There was a recent story on /. about a company that bought a little known patent right before it expired, then went about suing everybody and anybody for infringement *after* the expiration, but going back 6 years for damages.

    --
    Is it just my observation, or are there way too many stupid people in the world?