Re: Prefix Delegation and hosts

[joel jaeggli <[e-mail]>]

On 7/20/17 13:45, Lorenzo Colitti wrote:
> On Thu, Jul 20, 2017 at 4:37 AM, Brian E Carpenter
> <[e-mail] <mailto:[e-mail]>> wrote:
> 
>     If it gets a /64 and
>     and chooses to use DHCPv6-PD to hand out /80s to its friends, nobody
>     upstream will know (or care). Of course, SLAAC won't work for the
>     friends,
>     but nobody upstream will know that either. (It should be a small matter
>     of coding to make SLAAC work with 48 bit IIDs, so I've no doubt that
>     will show up in running code sometime.)
> 
>  
> Why pick /80 instead of something more familiar such as /120? The
> requesting router can even assign prefixes based on RFC1918 IPv4 /24
> prefixes and IIDs based on the late 8 bits of the IPv4 address. Skip a
> few steps in the race to the bottom.

Presumably if your goal is to allow downstream devices to futher segment
you will assign the shortest prefixes you can get away with in your
model. if your goal is micro-segmentation of things like for example for
containers or VMs, you'll probably assign as long as you can get away
with e.g. /126 /127 /128  which can be littered all over the address
space if you're so inclined.

> 
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