IPv6 Prefix Allocation
Discussions center on IPv6 address space allocations, particularly ISPs handing out /64 prefixes to customers, debates on their size relative to needs, and comparisons to IPv4 private ranges like RFC1918.
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They will probably give you an entire /64 subnet. You can use 2^64 devices. It will be fine :)
Why do we need more RFC1918 addresses? What's wrong with 10.0.0.0/8?
/64 is a lot of addresses. That's 2^32 internets.
How about 224.0.0.0/4? There are vastly more addresses going to waste up there...
Oh boy, we're gonna need more than 4,294,967,296 IP addresses!
You're technically correct, but ISPs best practice is to hand out a /64.
You can get /24's (256 addresses), you don't need to get a /22. Anything with a longer prefix is not generally allocated by regional internet registries, and won't usually be accepted over BGP.
Did you mean /24? As low as /16 is valid, but /8 includes plenty of public addresses.
On the ISP side, you get a ton of space. As a consumer on residential broadband, you get a limited amount of space. I have a /40 and assign down to a /127 for Point to Point links in a datacenter. IPv6 is still an older standard and a lot of assumptions were built in about a /64 being the smallest subnet. Some routers didn't support a /127 for PtP until recently even though it was an RFC in 2010. I think even NAT66 was discouraged until everyone realized you cann't
Nice, limits for ipv6 are for a /64 and there's quite a lot of those in a /48...