Subject: [radext] Re: New I-D: draft-seralathan-radext-persistent-devid-00
From: Alan DeKok <[email-masked]>
To: "Premanand Seralathan (pseralat)" <pseralat=[email-masked]>
Cc: "[email-masked]" <[email-masked]>
Date: Tue, 26 May 2026 06:50:44 -0400
List-Id: RADIUS EXTensions working group discussion list <radext.ietf.org>

On May 25, 2026, at 11:42 PM, Premanand Seralathan (pseralat) <pseralat=[email-masked]> wrote:
> The NAS doesn't need to correlate across connections — the server does. On reconnect with a new MAC, the same certificate yields the same UUID server-side. The NAS caches Persistent-Device-Id for the current session, echoes it in accounting, and shares it with integrated platforms (profiling engines, location services) so they can identify the endpoint across MAC changes. Will clarify this in -01.

  Thanks.

  This functionality could be done by a RADIUS proxy, so the NAS doesn't have to be modified.  That would make it much easier to deploy.

  Alternately, since this proposal provides for device tracking, it could just be done with CUI.  i.e. instead of sending a new attribute, just send:

	Chargeable-User-Identity = <persistent-device-id>@<realm from User-Name>

  Or since most User-Names are "@realm" or "anonymous@realm", the IdP can reply with

	User-Name = <persistent-device-id>@<realm from User-Name>

  And then the functionality works, without changing anything else in RADIUS.  The main downside here is that there's no separate attribute for persistent device ID.  But I think the main goals of the document are met.

  Alan DeKok.