Joao Luis Silva Damas wrote:
Brian,
At 10:29 -0500 7/7/00, Brian E Carpenter wrote: ...snip...
A /64 for dialup is also too rigid because the way technology is going a /64 is not going to be enough subnets for what wiill be a dial up connection with a large lan behind it.
Indeed. But that isn't an issue the RIRs need to think about.
It is not the RIRs trying to force variable length prefixes. At the RIPE meeting in Budapest and the ARIN meeting in Calgary we reported what the outcome of conversations with IETF people was (the /48, /56, /64 options for allocation). This seemed to be a reasonable way of doing it for the IPv6/ngtrans IETF people and to the RIR people present in Adelaide.
At both the ARIN and RIPE meetings, ISPs (the people who will use the address space, after all) were the ones that suggested variable length prefixes for allocation and the RIRs must go by the community consensus (BTW, at the RIPE meeting no consensus was reached, with both the variable length and the 3 fixed lengths having supporters).
A second issue is to think about a way of getting the IETF IPv6 people and the 3 RIR communities to talk to each other at the same, otherwise we are entering a loop, with at least 4 separate discussions and each dependant on the other 3.
The only practical reason I can see for variable-length prefixes is for the ISP to charge more money for allocation of any prefix shorter than a /64. Guaranteed, the average ISP (no, I won't tar you all with the same brush) if permitted to allocate a /64 won't allocate anything shorter unless lubricated with many times the amount of cash. Perhaps it sounds cynical, but that's based on my experiences with ISPs. Under IPv4, I can see how a scarce resource falls under the supply/demand paradigm. Let's not falsely inflate the value of a /48 to the end-user by making longer prefixes available. Those longer prefixes will simply become the norm, which was not our intent, was it? D