Subject: draft-ietf-krb-wg-kerberos-clarifications-03.txt 3.2.6

From: "Joel N. Weber II" <[email-masked]>
Date: Tue, 10 Jun 2003 23:23:18 -0400

In looking at 3.2.6. Using the encryption key, I understand more
clearly why my idea of the meaning of session key and sub-session key
doesn't match Sam Hartman's idea of the terms.

The first sentence of that section, ``After the KRB_AP_REQ/KRB_AP_REP
exchange has occurred, the client and server share an encryption key
which can be used by the application.'', is clearly talking about
``the session key'', but it doesn't call it ``the session key'', which
does not help to establish that use of terminology.

The phrase `true session key' appears in quotes.  Apparently a `true
session key' can either be a session key or a sub-session key.  If a
sub-session key is not a session key, it is extremely confusing that a
sub-session key can be a `true session key'.  I think it would be best
if some term that does not include the word ``session'' were used for
the key that happens to be used by KRB_SAFE and KRB_PRIV; perhaps the
term ``encryption key'' should be used for that, although perhaps a
key used only for integrity protection is not really an encryption key.

The glossary never states that a sub-session key is also refered to as
a subkey, and section 3.2.6 only uses the term subkey and never
sub-session key.  This does not facilitate the use of the text search
when looking for the relevant part of the document.

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From: Nicolas Williams <[email-masked]>
Date: Wed, 11 Jun 2003 10:10:53 -0700

I think the text in the introduction, section 1 paragraph two, makes
this quite clear, and it's right in the beginning of the document.

I searched the document for "session" and "sub-session" and that was the
first thing that came up.

I don't think the relation of sub-session keys to session keys needs any
further clarification.

Also, there is no section of the draft title "Glossary", in fact, the
word does not appear anywhere in the text.

Cheers,

Nico
--

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From: Clifford Neuman <[email-masked]>
Date: Wed, 11 Jun 2003 10:25:34 -0700

It is good to see the changes coming in for the clarifications
document.  I will have another ID ready incorperating these by this
coming Friday (two days from now).

Cliff

   Date: Wed, 11 Jun 2003 10:10:53 -0700
   From: Nicolas Williams <[email-masked]>

   Cheers,

   Nico
   --

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From: "Joel N. Weber II" <[email-masked]>
Date: Wed, 11 Jun 2003 16:34:09 -0400

> I don't think the relation of sub-session keys to session keys needs any

While I agree that the text in the introduction is reasonable, I don't
think that its presence is a reasonable excuse for keeping the text
later in the document in its current confusing state.

> word does not appear anywhere in the text.

I don't understand how you're concluding this, as I see this heading:

1.6. Glossary of terms

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From: Nicolas Williams <[email-masked]>
Date: Wed, 11 Jun 2003 13:41:05 -0700

> later in the document in its current confusing state.

The description of "Session key" in the glossary (yes, I know, see
below) could stand a small improvement - it could read:

   Session key
      An encryption key, carried by a Ticket and generated by KDCs,
      which can be used for session integrity and privacy protection as
      well as for negotiating per-session keys called "sub-session"
      keys.

> I don't understand how you're concluding this, as I see this heading:

I thought I was doing a case-insensitive search.  Sigh.

Cheers,

Nico
--

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From: Sam Hartman <[email-masked]>
Date: Thu, 12 Jun 2003 01:02:41 -0400

>>>>> "Joel" == Joel N Weber <[email-masked]> writes:

    >> I think the text in the introduction, section 1 paragraph two,
    >> makes this quite clear, and it's right in the beginning of the
    >> document.
    >> 
    >> I searched the document for "session" and "sub-session" and
    >> that was the first thing that came up.
    >> 
    >> I don't think the relation of sub-session keys to session keys
    >> needs any further clarification.

    Joel> While I agree that the text in the introduction is
    Joel> reasonable, I don't think that its presence is a reasonable
    Joel> excuse for keeping the text later in the document in its
    Joel> current confusing state.

I might agree with this comment before the last call was ended, but I
disagree that this issue is worth revisiting now.