Re: [radext] BoF request for IETF 115 Fri, 30 September 2022 12:08 UTC

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To: 'Alan DeKok' <>, 'Stefan Winter' <>
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Date: Fri, 30 Sep 2022 13:08:44 +0100
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Subject: Re: [radext] BoF request for IETF 115
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> > From what I see in operations, the biggest problem people have with
> > certificates seems to be that they have an expiry date you need to
attend to.
>   I agree 110%.  It's the biggest issue with certificates.
>   Using a private CA is awkward, but isn't too bad.  Using public CAs is
> more difficult.

And operating a private CA is much more difficult than PSKs. Moreover,
credentialing a large NAS estate with client certs could be a lot of effort.
And, from operator experience, many folks simply don't understand client
certificates and key management. Conversely, PSKs are intuitive.

> > If PSKs are too low-entropy then one of the more recent public/private
> keypair constructs could be an alternative: RFC7250, "Using Raw Public
> in TLS and DTLS".

RFC7250 assumes out of band key provisioning. Again, I think provisioning
keypairs on a server and client would stretch most users. With PSK, it is
the same key on both entities. It is hard to get this wrong.

I have no objection to some form of public key based authentication; but we
need support for PSKs or this will be too hard for most users.