The IETF IPv6 allocation scheme was crazy from the start. The standard subnet size for autoconfiguration purposes is /64 = 18 Billion Trillion addresses. Of course reality is that autoconfiguration is only marginally useful and lots of things like servers and infrastructure links are statically assigned or assigned through dhcpv6. Most of the time I assign /112's to server subnets to limit the risk of IPv6 neighbor discovery attacks.
The standard /48 assignment size from ISP's to end-users was targeted mainly at stingy residential ISP's that were only assigning one IP per customer. They wanted any customer to have as many publicly routable subnets as they would ever need or want, but 65k is a lot of subnets. This was later updated to a default of /56 (256 subnets) but you could still get at /48 just for asking.
It got even weirder on RIR to ISP portable allocations. One of the original schemes would have RIR's allocating a "TLA" /16 (!) to only a few mega ISP's. Most ISP's/hosts would have to get their "NLA" address blocks from and be subservient to the 800 pound gorillas in the industry. https://www.rfc-editor.org/rfc/rfc2450.txt, https://www.rfc-editor.org/rfc/rfc2374
This was loosened somewhat in 2000 with RFC2928 which designated a "Sub-TLA" /29 as the initial ISP size. This would open it up to many more potential registrants, at least in theory. https://www.rfc-editor.org/rfc/rfc2928.html
The TLA/Sub-TLA/NLA system was abandoned in 2003 with RFC3587 after panic set in that nobody was deploying IPv6. https://www.rfc-editor.org/rfc/rfc3587.txt. ARIN had only made 30 Sub-TLA assignments by the end of 2002.
While RFC3587 wisely punted allocation policy to the RIR communities, the RIR's still had very restrictive policies inherited from RFC2450. Only around 2004 did they loosen to the point that ordinary networks could start requesting addresses. Google for example got their first IPv6 allocation in 2005. The problem is by then few networks were interested or just assumed they wouldn't qualify. When I got my first /32 in late 2004 there were less than 1000 routes in the global IPv6 table! Today there are ~135,000.
These more permissive rules only applied to ISP's/Hosts. End user orgs of any size were not allowed to start requesting portable /48's directly from RIR's until 2006 after much debate in RIR communities and vocal objections from IETF members and certain large ISP's.
Today router silicon and RIR policies have converged to a reasonably functional state. Too bad it took 20 years to get here or IPv6 might actually be on it's way to replacing IPV4. Instead that is still about 20 years away.
The standard /48 assignment size from ISP's to end-users was targeted mainly at stingy residential ISP's that were only assigning one IP per customer. They wanted any customer to have as many publicly routable subnets as they would ever need or want, but 65k is a lot of subnets. This was later updated to a default of /56 (256 subnets) but you could still get at /48 just for asking.
It got even weirder on RIR to ISP portable allocations. One of the original schemes would have RIR's allocating a "TLA" /16 (!) to only a few mega ISP's. Most ISP's/hosts would have to get their "NLA" address blocks from and be subservient to the 800 pound gorillas in the industry. https://www.rfc-editor.org/rfc/rfc2450.txt, https://www.rfc-editor.org/rfc/rfc2374
This was loosened somewhat in 2000 with RFC2928 which designated a "Sub-TLA" /29 as the initial ISP size. This would open it up to many more potential registrants, at least in theory. https://www.rfc-editor.org/rfc/rfc2928.html
The TLA/Sub-TLA/NLA system was abandoned in 2003 with RFC3587 after panic set in that nobody was deploying IPv6. https://www.rfc-editor.org/rfc/rfc3587.txt. ARIN had only made 30 Sub-TLA assignments by the end of 2002.
While RFC3587 wisely punted allocation policy to the RIR communities, the RIR's still had very restrictive policies inherited from RFC2450. Only around 2004 did they loosen to the point that ordinary networks could start requesting addresses. Google for example got their first IPv6 allocation in 2005. The problem is by then few networks were interested or just assumed they wouldn't qualify. When I got my first /32 in late 2004 there were less than 1000 routes in the global IPv6 table! Today there are ~135,000.
These more permissive rules only applied to ISP's/Hosts. End user orgs of any size were not allowed to start requesting portable /48's directly from RIR's until 2006 after much debate in RIR communities and vocal objections from IETF members and certain large ISP's.
Today router silicon and RIR policies have converged to a reasonably functional state. Too bad it took 20 years to get here or IPv6 might actually be on it's way to replacing IPV4. Instead that is still about 20 years away.