Re: Extending a /64

[Mark Smith <[e-mail]>]

On Tue, 17 Nov 2020, 14:39 Brian E Carpenter, <[e-mail]>
wrote:

> Excuse front posting:
>
> > Whether or not the addresses used in the control systems of aircraft are
> announced to the Internet, it seems completely justified to use globally
> unique address space to address them.
>
> I completely agree.


I think of that approach as the IPv4 one because RFC1918s weren't unique.

As ULAs are pseudo globally unique, I see very little reason if any to use
GUA space for private disconnected networks.

I haven't looked at router spec sheets in a while, however typical core
routers can do 1 million IPv4 routes, so assuming a quarter of that for
IPv6, 250 000 /48 ULAs or 16 billion /64s.

Regards,
Mark.




That isn't where the issue lies. It's in the proposal to include 39
> non-topological bits in the routeable prefix, which goes against 25 years
> of CIDR.
> (28 years if we respect RFC1338 as the origin document.)


> Regards
>    Brian Carpenter
>
> On 17-Nov-20 15:55, David Farmer wrote:
> >
> > On Sun, Nov 15, 2020 at 2:56 PM Mark Smith <[e-mail]
> <mailto:[e-mail]>> wrote:
> >
> >
> >     On Mon, 16 Nov 2020, 07:19 Philip Homburg, <
> [e-mail] <mailto:[e-mail]>>
> wrote:
> >
> >         > Again, there are 35 trillion /48s in 2000::/3. How many would
> you
> >         > need?
> >
> >         It gets tight when you want the prefix to contain 39 bits to
> number around
> >         half a million planes.
> >
> >
> >     Why are half a million planes going to be on the Internet?
> >
> >
> > Being on the Internet is not the only justification for the use of
> globally unique address space.
> >
> > You mention that airplanes can fall out of the sky, it would be really
> bad if an airplane every fell out of the sky, or collided with another
> airplane, because of an address conflict. The proper used globally unique
> registered address space makes such a conflict almost impossible. Where the
> use of ULA makes such addressing conflicts statistically possible, even if
> unlikely. With half a million aircraft and the potential consequences of an
> address conflict, the ULA random selection algorithm is probably not a good
> idea for this use case.
> >
> > Whether or not the addresses used in the control systems of aircraft are
> announced to the Internet, it seems completely justified to use globally
> unique address space to address them. Further, a single very large
> allocation something like a /16 or more to the international coordinating
> body for the aircraft industry, allowing them to make sub-allocations to
> aircraft operators, airport operators, navigational aid operators, etc...
> seems like a quite reasonable address management scheme to me.
> >
> > There are several ways to accomplish this; the IETF could make a special
> allocation, a global policy could be coordinated through the RIRs and the
> ICANN ASO, or the entity could approach one of the RIRs for an allocation
> directly. As a past member of the ARIN AC, I know for a fact that ARIN IPv6
> policy explicitly contemplates LIRs that are not necessarily connected to
> the Internet, and contemplates generous initial allocations of up to a /16
> for LIRs when justified. Further, ARIN uses a sparse allocation
> methodology, reserving at least an additional nibble of address space for
> future expansion.
> >
> > Honestly, given the importance of the use case discussed, I don't see
> the controversy, the allocation of a large address space allowing for the
> assignment of /48s or /56s to aircraft and /48 or larger to airports seems
> easily justified, and allocating it out of something other than 2000/3
> seems quite reasonable as well, which would require IETF action. Further,
> the use of IIDs other than /64 is completely unnecessary.
> >
> > Thinking even more broadly it might not be a bad idea to allocate a
> whole new /4 for transportation automation to cover aircraft, cars, trucks,
> intelligent roadways, etc...
> >
> > Thanks
> > --
> > ===============================================
> > David Farmer               Email:[e-mail] <mailto:
> [e-mail]>
> > Networking & Telecommunication Services
> > Office of Information Technology
> > University of Minnesota
> > 2218 University Ave SE        Phone: [phone]
> > Minneapolis, MN 55414-3029   Cell: 612-812-9952
> > ===============================================
> >
> > --------------------------------------------------------------------
> > IETF IPv6 working group mailing list
> > [e-mail]
> > Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6
> > --------------------------------------------------------------------
> >
>
>