Re: [802.21] Security SG: Definition of Administrative Domain
Hi Gabor,
On Mon, Dec 10, 2007 at 04:51:20PM -0600, Gabor Bajko wrote:
> Yoshi,
>
> A domain can be administered in different ways. Administering only the
> keys, the subscription, the roaming agreements, any combination of
> those, etc. Administrative domain is too broad and vague term in my
> opinion.
I still think the proposed defition works. Please see my comment below.
>
> The specific comment I had relates to this sentence from your proposal:
>
> "A collection of End Systems, Intermediate Systems, and authority.
> > The components which make up the domain are assumed to interoperate
> > with a significant degree of mutual trust among themselves"
>
> One can read the above in a way that any two End Systems within the
> domain have some kind of mutual trust. It is true that there is mutual
> trust between any end system and the authority (including intermediate
> systems) but not between two end systems.
If my computer is attached in my corporate network, then I can trust
other computers including servers and other employee's computers in
the corporate network to run some applications (Windows file-share,
VoIP, etc.) on them. In a large-scale enterprise network, the trust
may be hierarchically formed, but that is also covered in the
definition.
>
> Even if we clarify the definition in this respect, I will hardly be able
> to map this abstract definition to the use cases discussed in .21
> security SG.
To use the definition for our use cases, if an MN belonging to a
particular administrative domain attaches to a PoA of the same
administrative domain, there will be authentication and authorization
signaling within the administrative domain, but is no external
signaling with other administrative domains. On the other hand, if
the MN first attaches to a PoA in a visited administrative domain,
then the PoA's administrative domain is suspicious about the MN, and
thus external authentication and authorization signaling with the MN's
administrative domain will happen to create a mutual trust between the
MN and the visited administrative domain so that MN can be part of the
visited administrative domain.
Regards,
Yoshihiro Ohba
>
> - gabor
>
> -----Original Message-----
> From: ext Yoshihiro Ohba [mailto:yohba@tari.toshiba.com]
> Sent: Monday, December 10, 2007 11:02 AM
> To: Bajko Gabor (Nokia-SIR/MtView)
> Cc: yohba@tari.toshiba.com; STDS-802-21@LISTSERV.IEEE.ORG
> Subject: Re: [802.21] Security SG: Definition of Administrative Domain
>
> Hi Gabor,
>
> If my understanding is correct, HOKEY WG is trying to define their
> notion of domain because they define a domain-specific root key (DSRK)
> and they need to have a clear definition on what "domain" is in term of
> DSRK.
>
> Since we (802.21 Security SG) are not defining DSRK, we don't need to
> define a key management domain at least in the course of "study", and a
> more general term "administrative domain" would be sufficient, IMO.
>
> Also, end systems in the same administrative domain are assumed to
> interoperate with mutual trust even if the administrative domain is
> defined in terms of AAA operation. Otherwise, how a NAS in a AAA realm
> can trust the authorization result sent by the AAA server in the same
> AAA realm? Note that existence of mutual trust still requires mutual
> authentication between end systems in the same administrative domain.
>
> Regards,
> Yoshihiro Ohba
>
>
> On Mon, Dec 10, 2007 at 11:23:17AM -0600, Gabor.Bajko@nokia.com wrote:
> > Yoshi,
> >
> > Based on the discussions we had in HOKEY last week, I am not sure this
>
> > is a good definition.
> >
> > Why would we want to say that end systems are assumed to interoperate
> > with mutual trust? That is not true today in a AAA based
> > administrative domain. Besides, we probably should look at the
> > definition of a 'key management domain', rather than an
> 'administrative domain'.
> >
> > It may be easier to find a definition if we scope it down to the
> > context.
> >
> > - gabor
> >
> > -----Original Message-----
> > From: ext Yoshihiro Ohba [mailto:yohba@TARI.TOSHIBA.COM]
> > Sent: Wednesday, December 05, 2007 6:16 PM
> > To: STDS-802-21@LISTSERV.IEEE.ORG
> > Subject: [802.21] Security SG: Definition of Administrative Domain
> >
> > We have a home work raised in November meeting to revise the
> > definition of Administrative Domain (AD).
> >
> > RFC 1136 has a good definition of AD. Here is revised definition of
> > AD with borrowing and slightly modifying text in RFC 1136:
> >
> > "
> > Administrative Domain
> >
> > A collection of End Systems, Intermediate Systems, and authority.
> > The components which make up the domain are assumed to interoperate
> > with a significant degree of mutual trust among themselves, but
> > interoperate with other Administrative Domains in a mutually
> > suspicious manner.
> >
> > Administrative Domains can be organized into a loose hierarchy
> > that reflects the availability and authoritativeness of
> > authentication and authorization information. This hierarchy does
> > not imply administrative containment, nor does it imply a strict
> > tree topology.
> > "
> >
> > I believe this addresses all issues related to administrative domain
> > definition.
> >
> > Comments?
> >
> > Yoshihiro Ohba
> >
> >
> >
>
>