Privacy Extensions for Stateless Address Autoconfiguration in IPv6
On Mon, 7 Dec 2020 at 05:18, Ed Greshko <ed.greshko@greshko.com> wrote:
On 07/12/2020 11:11, Tim via users wrote:
> On Sun, 2020-12-06 at 15:43 -0400, George N. White III wrote:
>> As more systems use IPv6,  bad actors will have to collect
>> active IPv6 addresses.  You may be one of the first to see that
>> start.
> I have to wonder how that's going to go.  With IPv4 most people were
> behind NAT (which isn't a firewall but does get in the way of external
> traffic).  IPv6 is supposed to aid us in not needing to do NAT anymore,
> so more things could be directly addressable from the outside world.  A
> nd understanding IPv6 addresses is more complicated.
>   

On the subject of "collect active IPv6 addresses", that is rather a complicated issue.

That just means service providers can charge more for data that links IPv6's to customers
by time-intervals.
 

Unlike IPv4 and DHCP deployment by ISPs which tend to result in the same IP address being
assigned to users.  I've noticed that ISPs tend to use IPv6 Stateless Address Autoconfiguration (rfc4862).
If you check the email headers from home_user you'd see that he has a different IPv6 address
on different days.

Again, adds value to ISP's data.  There is rfc4941 -- Privacy Extensions for Stateless Address
Autoconfiguration in IPv6
 

His ISP is Comcast and the IPv6 address space they have is 2001:558:6040::/48.  That address space
has 1208925819614629174706176 addresses.  Of course the ISPs will segment this address space
so the address space in a user's area will be less, but not insignificant.

I happen to have contracted with my ISP for fixed IPv4 and IPv6 addresses.  The address space
assigned to me for IPv6 is 2001:b030:112f:0000::/56 or 4722366482869645213696 addresses.
I've segmented this into 256 networks of /64 where each subnet has 18,446,744,073,709,551,616
addresses.

Address hopping (6HOP) might add enough complexity to blow up your ISP's database:

https://publications.sba-research.org/publications/201707%20-%20JUDMAYER%20-%20LightweightAddressHopping.pdf

Wondering what the CO2 footprint of IPv6 address generation will be?
--
George N. White III