OpenID Extension is defined in the section 12 of the OpenID Authentication 2.0 as:

An Extension to OpenID Authentication is a protocol that “piggybacks” on the authentication request and response. Extensions are useful for providing extra information about an authentication request or response as well as providing extra information about the subject of the authentication response.

OK. My question: Does it entirely have to depend on authenticaiton request and response, or can it partially depend on it?

By definition, I think it is the later, because, the subsequent paragraph goes:

OpenID extensions are identified by a Type URI. The Type URI MAY be used as the value of an element of an OpenID element in an XRDS document associated with a Claimed Identifier. The Type URI is also used to associate key-value pairs in messages with the extension.

Clearly, this is not authentication request (section 9) and response (section 10), but Discovery (seciont 7.3). Thus, if it were to be entirely on request and response, the spec contradicts itself.

Therefore, it has to mean that an extension is a protocol that has to utilize request and response.

QED

I should be doing this more often:

Japan

- CX discussion group has produced use cases and requirement document on Creative Commons License. Contributors are

Yoichi Ohnawa, NEC BIGLOBE, Ltd.
Takaya Tanaka, KDDI Corporation
Daisuke Ikeda, JCB Co, Ltd.
Takayuki Komatsu, SoftBank BB Corp.
Toru Hada, NEC Corporation
Tatsuo Kudo, Nomura Research Institute Ltd., Editor
Nat Sakimura, Nomura Research Institute, Ltd.
Taizo Matsuoka, Yahoo Japan Corporation
Naoki Koshikawa, Rakuten, Inc.

- Payment Discussion Group is starting in a few week.
As an off spring of the CX Discussion Group, Payment Discussion Group
is starting in Tokyo. It will first evaluate the recent change in the
payment law in Japan, then subsequently disucss the applicability
of OpenID and related technologies on it.

- Ministry of Internal Affairs and Communication has published a request for public comment on the coming substantiative experiment which involves OpenID and SAML interop and uses in Telecos and other entities. (Aug. 6)

- Ministry of Economy, Trade and Industry has put a tender for substantiative experiment on Government-Private Sector Authentication and Identity interoperability, which is likely to be OpenID. (Aug. 4)

- NRI and Verisign Japan announced their intent to start high assurance authentication service based on mobile phone identification, risk based authentication, etc. over OpenID. (Aug. 6)

- NTT has announced that it will support OpenID as “NTT Single Signon Service”. When the service opens, it will be the largest OpenID provider in Japan with over 70 million users. (May 12)

- Numerous miscellaneous press coverages and seminars. We stopped counting them at OIDF-J because there are too many now. OIDF-J now has 52 member companies spanning from the telcos, banks, retailers, transportation, IT, etc.

Europe

- In June, Robert Ott has become the Vice President of OIDE, and is the acting head of OIDE now, as Snorri is extremely busy right now to run his family’s business after his father passed away late last year.

- Jean-Noel Colin is now the representative for Belgium

- OIDE will be representing OpenID in OpenID at EMEX Suisse.

- In autumn, Robert Ott will present OpenID at a Security Event in the IBM innovation center here in Switzerland.

- The major Dutch social website Hyves released it’s support for OpenID in April.

- “OpenID, put into practice” held in Amsterdam, May 12, was a great success.

- CloudViews 2009 held in O Porto, where Nat Sakimura was an invited speaker on identity.

- The largest Portuguese Portal now supports OpenID.

I am pretty sure I am missing many important news. Please let me know so that I can keep the list updated.

Here is my first cut to the Contract Exchange 1.0 (CX) Draft. It is unfinished, and has lots of places needs text, but essence is there, I think.

From this morning, there is a thread going on on Identity Commons mailing list (identity gangs) on “What is Identity?”.

The thread started off by quoting Kim Cameron’s definition of Digital Identity.

Digital Identity: the digital representation of a set of claims made by one digital subject about itself or another digital subject.

Then, Bob Blakly paraphrases American Heritage Dictionary in the same thread as:

the set of characteristics by which a thing is generally recognized or known

These two seems to be in a general agreement, but I would like to dig a little more because I have a bit of problem with this definition.

When we talk about a term, it is always useful to get back to its root. The below is an excerpt from my lecture at Security Expo 2009 Tokyo.

---

The term “identity” first appeared in documents around 1570. It was a term that was derived from middle age french word identité, which was in tern formed from 5th century Latin Identitatem. Identitatem was a combined word of “idem et idem”, where “idem” is “same”. From this, it is apparent that the central notion of “identity” in fact is the “sameness”.

This is captured in the “Principle of Identity of Indiscernibles” by Gottfried Wilhelm Leibniz, (1646 ? 1716) .

Subject x and y are identical if any predicate possessed by x is also possessed by y and vice versa.

i.e.,

(1)

This is rather controversial.

Clearly, The indiscernibility of identicals:

(2)

holds, but not the identity of indiscernible.

To illustrate it, I have depicted the relationship between Subject and identity (partial identity) in the following figure.

In this figure, I have represented Subject as a molecular structure. It is there, but we cannot observe it directly because whenever we observe, it is merely a projection of it onto the cognitive surface or hyper-plane. Unfortunately, this mapping/projection is not one-to-one. Different Subject can map onto the same thing on a cognitive surface/hyper-plane, i.e.,

Two objects having same identity may NOT be identical.

This sound contradictory.

From (1) and (2), it is clear that to have the proposition

Two objects having same identity is identical

hold, it has to be Subject=Identity.

Of course,

Two objects having same partial identity may NOT be identical.

We sometimes call this “Partial Identity” a “Persona”.

The problem of American Heritage definition probably is that it is supposing there is a general cognitive plane (generally recognaized). There is no such thing in practice, unfortunately.

References:
Definition of identity?, http://lists.idcommons.net/lists/arc/community/2009-08/msg00000.html
Identity of Indiscernibles, http://en.wikipedia.org/wiki/Identity_of_indiscernibles