Subject: Re: 64-bit identifiers

From: "J. Noel Chiappa" <[email-masked]>
Date: Thu, 9 Aug 2001 12:11:56 -0400

> From: Bob Hinden <[email-masked]>

    > I suspect that any new scheme using global identifiers will have to
    > deal with privacy issues to allow for anonymous communication.

If you look at things like HIP, they provide identifiers that are both
completely anonymous as well as long-lived and globally unique. It's now
understood that the abiltity to provide anonymity is a requirement.

Of course, for the really paranoid, they don't like long-lived unique
identifiers of any kind, because they allow correlation of activity, which
may allow identification through out-of-channel means. So for them, there's
*no* identifier scheme that will keep them happy. Kind of hard to work around
that requirement....

On the other hand, I have it on good authority that various commercial
activities are now tracking people on dialins without use of any kind of
identifier (e.g. HTML cookies) - they do it by some sort of activity
analysis. So the cost/benefit analysis (pro, utility of long-lived global
name, con, security issues) may still tip toward providing them (with a tip
of the hat toward the anonymity issue, which is relatively easy to provide,
of course).

And of course, for the really paranoid, they can just keep creating new
ones for every transaction.... :-)

	Noel

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From: RJ Atkinson <[email-masked]>
Date: Thu, 09 Aug 2001 13:34:11 -0400

At 12:11 09/08/01, J. Noel Chiappa wrote:
>On the other hand, I have it on good authority that various 
>commercial activities are now tracking people on dialins without 
>use of any kind of identifier (e.g. HTML cookies) - they do it 
>by some sort of activity analysis. So the cost/benefit analysis 
>(pro, utility of long-lived global name, con, security issues) 
>may still tip toward providing them (with a tip of the hat 
>toward the anonymity issue, which is relatively easy to provide,
>of course).

Quite so.  A number of commercial web firms have hired folks
who really understand traffic analysis techniques.  These are
now reasonably widely deployed to track web users/uses from at
least 2 commercial firms that I'm aware of.

Many of the "privacy advocates" don't seem to grasp that the
original IPv6 use of the MAC in the low-order bits wasn't the
big privacy threat -- traffic analysis has always been the 
bigger threat and the IPv6 spec change (though needed to pacify
those "advocates") can't actually resolve that privacy issue.

The world seems like a complicated place these days...(sigh).

Ran
[email-masked]

---

From: Erik Nordmark <[email-masked]>
Date: Mon, 13 Aug 2001 10:41:32 +0200 (CEST)

> *no* identifier scheme that will keep them happy. Kind of hard to work around

If a node can have multiple such indentifiers, new identifiers can be
created autonomously by the node, and it isn't too expensive
to create new ones, then it wouldn't be infeasible for the truly paranoid
to use a different identifier every hour or for every connection.

Thus I think the ability to autonomously create new identifiers is a 
requirement.

  Erik