IPv6 end user addressing

Mikael Abrahamsson swmike at swm.pp.se
Fri Aug 5 11:29:52 CDT 2011

On Fri, 5 Aug 2011, Brian Mengel wrote:

> In reviewing IPv6 end user allocation policies, I can find little
> agreement on what prefix length is appropriate for residential end
> users.  /64 and /56 seem to be the favorite candidates, with /56 being
> slightly preferred.

Not slightly preferred, very much preferred. /56 is future proof and works 
for "everybody". /64 is short sighted and doesn't allow for multiple 
networks in the home.

> I am most curious as to why a /60 prefix is not considered when trying
> to address this problem.  It provides 16 /64 subnetworks, which seems
> like an adequate amount for an end user.

Why save on addresses, you can just get more IPv6 addresses if you need 
them. /56 is allowed per user from all the RIRs afaik.

> Does anyone have opinions on the BCP for end user addressing in IPv6?

Yes, there are plenty of people with opinions.

This has been hashed over and over and over again, please check the 
archives for lots of discussions on pros an cons. If you want to do it 
right, go for /56, it works.

Mikael Abrahamsson    email: swmike at swm.pp.se

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