potential new IETF WG on anonymous IPSec

[Bill Stewart]

At 12:57 PM 9/9/2004, Hal Finney wrote:
> >       http://www.postel.org/anonsec
>
>To clarify, this is not really "anonymous" in the usual sense.  Rather it
>is a proposal to an extension to IPsec to allow for unauthenticated
>connections.  Presently IPsec relies on either pre-shared secrets or a
>trusted third party CA to authenticate the connection.  The new proposal
>would let connections go forward using a straight Diffie-Hellman type
>exchange without authentication.  It also proposes less authentication
>of IP message packets, covering smaller subsets, as an option.

I read the draft, and I don't see how it offers any improvement
over draft-ietf-ipsec-internet-key-00.txt or Gilmore's proposal touse "open 
secret" as a not-very-secret pre-shared secret
that anybody who wants to can accept.
It does introduce some lower-horsepower alternatives for
authenticating less than the entire packet, and suggests
using AH which I thought was getting rather deprecated these days,
but another way to reduce horsepower needs is to use AES instead of 3DES.

Also, the author's document discusses protecting BGP to prevent
some of the recent denial-of-service attacks,
and asks for confirmation about the assertion in a message
on the IPSEC mailing list suggesting
    "E.g., it is not feasible for BGP routers to be configured with the
    appropriate certificate authorities of hundreds of thousands of peers".
Routers typically use BGP to peer with a small number of partners,
though some big ISP gateway routers might peer with a few hundred.
(A typical enterprise router would have 2-3 peers if it does BGP.)
If a router wants to learn full internet routes from its peers,
it might learn 1-200,000, but that's not the number of direct connections
that it has - it's information it learns using those connections.
And the peers don't have to be configured "rapidly without external 
assistance" -
you typically set up the peering link when you're setting up the
connection between an ISP and a customer or a pair of ISPs,
and if you want to use a CA mechanism to certify X.509 certs,
you can set up that information at the same time.



----
Bill Stewart  bill.stewart at pobox.com 

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