Not all providers are large enough to justify a /32.
----- Mike Hammett Intelligent Computing Solutions http://www.ics-il.com Midwest Internet Exchange http://www.midwest-ix.com ----- Original Message ----- From: "Philip Dorr" <tagn...@gmail.com> To: "Rob McEwen" <r...@invaluement.com> Cc: "nanog group" <nanog@nanog.org> Sent: Thursday, October 1, 2015 11:14:35 PM Subject: Re: How to wish you hadn't forced ipv6 adoption (was "How to force rapid ipv6 adoption") On Thu, Oct 1, 2015 at 10:58 PM, Rob McEwen <r...@invaluement.com> wrote: > On 10/1/2015 11:44 PM, Mark Andrews wrote: >> >> IPv6 really isn't much different to IPv4. You use sites /48's >> rather than addresses /32's (which are effectively sites). ISP's >> still need to justify their address space allocations to RIR's so >> their isn't infinite numbers of sites that a spammer can get. > > > A /48 can be subdivided into 65K subnets. That is 65 *THOUSAND*... not the > 256 IPs that one gets with an IPv4 /24 block. So if a somewhat legit hoster > assigns various /64s to DIFFERENT customers of theirs... that is a lot of > collateral damage that would be caused by listing at the /48 level, should > just one customer be a bad-apple spammer, or just one legit customer have a > compromised system one day. As a provider (ISP or Hosting), you should hand the customers at a minimum a /56, if not a /48. The provider should have at a minimum a /32. If the provider is only giving their customers a /64, then they deserve all the pain they receive.