Re: A common problem with SLAAC in "renumbering" scenarios

[Mikael Abrahamsson <[e-mail]>]

On Tue, 5 Feb 2019, Mark Smith wrote:

> I think a lot of this need in IPv4 has come from IPv4 addresses being
> precious and expensive resources. Consequently, it has been worth the
> expense and effort of fine grained management of them.
>
> In IPv6, that level of management isn't needed. Addresses are plentiful and
> cheap, so you can throw lots of address space at problems.

It's sometimes from re-farming of things. ISPs tend to today build largish 
access-routers and call them BNG. So when a 10GE interface is full, you 
need to split the customer load to two interfaces, or move some to a 
completely different router.

So if you move half of the subscribers of that port to a different router, 
now you have a problem because typically you'll have a set of 
addreses-space dedicated for that router and part of that now needs to go 
to another router. Typically you don't want this type of de-aggregation.

-- 
Mikael Abrahamsson    email: [e-mail]