Re: [Pidloc] PIdLoc Webex

[Tom Herbert <[e-mail]>]

On Fri, Dec 7, 2018 at 11:08 AM Dino Farinacci <[e-mail]> wrote:
>
> > Yes, the network should assign ephemeral addresses. Scaling this so
> > that hosts can use a different address per connection is the problem
> > that ensues.
>
> For the outer (or only header), you cannot get assigned ephemeral addresses. They need to be provider-assigned addresses so routing deeper in the network can aggregate such addresses into coarser prefixes.
>
> And note ISPs want to use uRPF so another reason for provider-assigned addresses. The best way to solve the *entire* problem is to tunnel with encryption from a point inside the ISP. Then the outer addresses are coarsified and the inner addresses are obfuscated.
>
> You could solve some of the problem with ILA but you need to keep translating the packet as it goes to the destination. And that will be hard to debug since it breaks traceroute.
>

You are convoluting the behavior of internal network operations with
the externally visible behavior. Think of it this way, we have end
hosts and we have Internet servers. The desired property wrt privacy
is that any host can use an untrackable source address per connection
to talk to any Internet servers. Servers on the Internet should not be
able to draw any correlation between any two flows, nor should they be
able to deduce geographic location with any accuracy. End hosts and
server only see these assigned addresses. They don't know about
mapping systems, underlays, encapsulation, or what the addresses mean
other. All they know is that the addresses than they identify a
communicating node and are routable in IP packets over the Internet to
some service provider. It is up to the network provider to support
this using mechanisms that scale, but the details of that are not
relevant to privacy as long as the desired external behavior is met
and privacy is maintained.

Tom

> Dino
>