Re: Analogy Units
"if all IPv4 addresses were contained inside a smartphone, IPv6 would fill a container the size of the Earth"
Sadly, this is nonsense. Because of the stupid and wasteful way that IPv6 addressing works, each LAN needs a /64 prefix (burning 2^64 addresses for typically a few dozen devices). And because it can't be subnetted on a longer prefix boundary, each subscriber who might need two or more subnets needs a larger allocation than that.
What it means is that in practice, an IPv6 /56 prefix is the same as an IPv4 single address with NAT - i.e. the unit that an ISP must give out to a "small" subscriber. Since the first three bits are fixed, this means that in practice that there are 2^53 usable IPv6 addresses. This is 2 million times (2^(53-32) = 2^21) more than IPv4; still a lot, but not mind-bogglingly vast.
The original plans assumed giving a /48 prefix to each subscriber. This would have meant that the IPv6 address space was only 2^13 times more than IPv4. IPv6 address depletion panic set in even before there were any users.
A few years ago, a single ISP - France Telecom - managed to get assigned a /19 of IPv6 address space. Remembering that the top 3 bits are fixed, this means they own 1/65,536 of the entire IPv6 unicast address space. And there are more than 65,536 autonomous systems making up the Internet today.
Clearly not everybody can justify a /19, but every member of RIPE gets a minimum of a /32, and can get a /29 on request with no questions asked.
Biting the hand that feeds IT
