Brian E Carpenter <[EMAIL PROTECTED]>: > > OK, I didn't intend to be emotional there. Let me try to explain. Until > we get something fundamentally different from the routing researchers, > the only model we have is BGP4, ...
i've heard of alternatives but you're right that nothing else has caught on. > ... and the only way we have to control the > growth in BGP4 table size and dynamics is aggregation. That's basic and > hasn't changed in 25 years. That's why CIDR saved us. no. i don't have objective measurements, but i know that a lot of table size control is achieved by limiting the horizon of announcements. ULA-C with my proposed diffs is just a way to take this a lot further, to legitimize it, to scale it up to planetary size. there's been a fundamental misunderstanding in the acadamy as to what actually happens in the field. ietf thought that the only connectivity that mattered was universal connectivity, and fought firewalls and nat for a long while, but ultimately firewalls and nat and RFC 1918 were all great things for the internet even though they "violated" the universal connectivity assumptions. for the record, table size only matters in the DFZ, and only because there are too many third parties for the budget of any one of them to govern the size of the table. away from the DFZ, table size is a self limiting problem, and no questions of aggregation are even pertinent. > So I really only see two kinds of IP prefix - those that aggregate and those > that don't. that's an extremely informative statement, thank you for sharing it. > We need to encourage the former and discourage the latter (as far as seeing > them in BGP is concerned). if you mean by "BGP", the DFZ, then i'd agree with this statement in isolation from the one that came before it. > In today's jargon, that means encouraging PA, and limiting PI to a few > thousand users that really need it. ULA-C with structure as you propose is a > form of PI. I believe it will be perceived as an easy way to get PI space, > and the pressure to stick ULA-C prefixes of this kind in the DFZ will become > very hard to resist. I don't see that risk being anywhere near as high for > current ULAs or for centrally registered random ULAs. harken back to the above where i referenced "many third parties". in the DFZ, what matters is what the tier-1 providers do. they can afford 2-megaroute forwarding machinery, they compete aggressively for end-sites against both other tier-1's and all of the regional or value-add or low-cost tier-2's, and they really like the PA concept because the renumbering penality gives them a form of lock-in that even microsoft and apple can only dream about. if the tier-1's decide to exchange ULA-C routes with each other, then the rest of the internet has to do likewise. and if some really large cash cow of a customer puts out an RFP to tier-1 saying "we'll buy bandwidth from whoever will route our ULA-C into the internet core" then it'll be very interesting. is this your proposed "pressure to stick" comes from? because i can think of a dozen reasons why it can't happen, all based on business strategy and self-interests of every single party involved in that money chain. the competing visions as i understand them are "random-prefix ULA-C makes it impossible to postprocess one's log files on computers outside the connectivity realm where they were gathered, makes recourse against spammers and ddos-for-hire crews even harder, and moves the hijacking problem from the realm where RPKI can help some day to the realm of ``i got it from agnes''(*)" and "assigned-prefix ULA-C makes it likely that the PI/PA separation regime will collapse, and take the internet down in flames." (*) http://www.lyricsdir.com/tom-lehrer-i-got-it-from-agnes-lyrics.html > I assume we all want the routing system to continue to scale at an > economically sustainable rate. Can you show that structured ULA-C will be > added to the DFZ at a sufficiently low rate that we won't get into > trouble? i predict that structured ULA-C will enter the DFZ at the rate of zero, since there will be an RFC which excuses anyone who wants to filter it out, and since there will be many more champions whose livelihoods are threatened by it than whose livlihoods could be enriched by it. (it's all about the money.) > What's your estimate of the total number of ULA-C prefixes needed? approximately one per family, worldwide, counting only the population who has electric power. much much higher than the 2-megaroute level, or the number of domain names registered in .COM and .DE (the two largest TLDs). > If those numbers fit within reasonable guesses about sustainable > DFZ growth, no problem. they don't fit, but they don't have to fit, because they're not going in. -------------------------------------------------------------------- IETF IPv6 working group mailing list [email protected] Administrative Requests: https://www1.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
