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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: What is the limit? (was RE: multi-homing fixes)
> > | If you had a router that could handle 2^32 prefixes, it will handle > | the IPv4 Internet. Forever. The whole growth curve argument is > | gone. > > Sure, just about anybody can build a router which has 2**32 forwarding > directives burned into ROM. It gets easier with fewer interfaces, too. > But, who wants a static network? > I do. and probably 99% of the userbase like me. Because, when *we* say static, we mean different to when you say static. Humpty Dumpty rules. Really, nobody wants dynamic routing. They just pretend its a feature, but given the amazingly static nature of cables in the ground and edge devices Kansas miraculously stays in the mid-west, I say in Brisbane mostly and what I want is a static declaration in the routing model of the world that says Brisbane is not in Kansas. And, based on what I hear from smarter people that is what BGP says. How much of the updates you see actually change anything about which of your links packets flow on? I bet its marginal change, not earth shattering change mostly. I mean, do you *WANT* to live on the edge of mt etna, or would you rather look at it from a stable place? Dynamic updates are chicken little. "THEY SKY IS FALLING! I CAN'T SEE <x>" followed 1/2 an hour later by "oh, yes I can" Better to say nothing to the world, and tell your next door friend who isn't under the cardboard sheet so they can help lift it for you. If you want dynamicism, do it locally please. > In the early 90s we had a network where you could wait a week > before the core of the Internet adapted to your topology change, > and changed its routing towards a particular prefix. It wasn't > really much fun. And guess what? Now we have a network where it can take two weeks to make an upstream edit their hand-crafted BGP and nothing has changed. Your point was? > > And neither can the rate of change. The problem only has to be Too Hard > to compute affordably, not NP-complete. This is like a mathematical version of Godwins law. But, there would appear to be people who assert its not unafordable to compute the routes for the current, and the forseeable network. so its neither NP complete nor unaffordable. Its also irrelevant because it looks like prefix collapse on the global /24 or /32 table is workable for most% of the world forever in internet terms. Saying CiDR makes BIFF admit the NETWORK FAILED is well, like BIFF. Just because its set in capitals, doesn't make it TRUE! > | "it's exponential and we'll never get ahead of it" is crap. It > | won't be forever, so let's get ahead of it. > > There's lots of irony in that too. Other than the hand-wave, > how do you propose to get (and stay) ahead of it? > > Sean. By filtering the /24's which when removed, drop > 1% < 20% of the routing table size (I invented those numbers) but lose >30% (I invented that one too) of the dynamicicsm of silly/pointless route annoucements, and appear to cause (after the two weeks of finding all the CNN like agencies on /24) a markedly marginal loss of connectivity for most% of the network. As if you also don't expect this to (a) work, and (b) continue to make previously believed exponential growth become more linear. Market forces also help. dotcom crash == merger & acquisitions == longterm baseline no questions asked handback for aggregation == less demand for new nets == less rate of growth of prefixes. rate of growth is measured in months and years. BGP updates are in tens of seconds. the relationships are not exactly 1:1 ratio are they? Its coming. Rant as much as you like, filtering is back on the agenda. And, I am willing to suggest once the brouhaha settles down, we all find it suprisingly pleasant afterwards. NOPEER is probably as relevant, because the /24 issue is about a more local horizon of announcement. As Geoff Huston says, NOPEER flies as far as your money. Randys /24 filters meet it at that point, and we all win. Mind you, those two weeks of CNN suing everyone in sight is going to be fun! My hope is this makes everyones mailfilters. I mentioned Godwins law so it should do. cheers -George
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