RE: [xri] Direct descendant vs. family descendant CIDs (was RE: [xri] Minutes: Special XRI TC Telecon Noon PT Friday 2007-08-24)

From
Chasen, Les <>
Date
2007-08-25T15:15:07+00:00
ID
Thread
RE: [xri] Direct descendant vs. family descendant CIDs (was RE: [xri] Minutes: Special XRI TC Telecon Noon PT Friday 2007-08-24)
Title: RE: [xri] Direct descendant vs. family descendant CIDs (was RE: [xri]
Minutes: Special XRI TC Telecon Noon PT Friday 2007-08-24)

We are beginning to get several **Id
elements but if their purpose is clear and unambiguous I am not sure how it
hurts interoperability.  The equivId concept is starting to grow on
me.  This is a nice way to publish identifiers to yourself in other
communities like linkedin, facebook etc.  

 

I am also growing warmer to the concept of
the other Id attribute that Drummond is currently calling useCID.  I am
completely against the current write up that says the value in this tag should
be used as the persistent cid by the consuming application.  I think this
is wrong to even imply to consuming applications.  They should use the cid
(the persistent primary key) of the XRD they queried.  I am however thinking
that it would be a powerful feature to be able to tell a consuming application
my preferred identifier.  This, along with equivId, provide a mechanism
for a consuming application to recognize me when I log in using different
identifiers.  That could be a strong mapping tool.

 

I encourage everyone to review http://wiki.oasis-open.org/xri/XriCd02/SynonymSemantics
 and add your opinions.   You will see a section at the bottom
where Wil and I have added some thoughts.  

 

contact: =les

voice: =les/(+phone)

chat: =les/skype/chat

pibb me  =les/+pibb

 

 

 

 

From: Barnhill,
William [mailto:] 

Sent: Saturday, August 25, 2007
9:53 AM

To: Markus Sabadello; Drummond
Reed

Cc: Chasen, Les;


Subject: RE: [xri] Direct
descendant vs. family descendant CIDs (was RE: [xri] Minutes: Special XRI TC
Telecon Noon PT Friday 2007-08-24)

 

 

As I mentioned in the earlier email I think we have
too many **Id elements and that it will hurt us in interoperability.  That
said I'd prefer direct desc. as well, for the same reason that Markus stated.

Bill

-----Original Message-----

From:  on behalf of Markus Sabadello

Sent: Fri 8/24/2007 8:51 PM

To: Drummond Reed

Cc: Chasen, Les; 

Subject: Re: [xri] Direct descendant vs. family descendant CIDs (was RE: [xri]
Minutes: Special XRI TC Telecon Noon PT Friday 2007-08-24)

I also think both is fine. In 99% of all cases it will be "direct"

descendants anyway.

Right now I have a slight preference for the tight version (NOT allowing

what you call "family" descendants), because with all those synonym
elements

we are discussing I feel there is really no need to mess with the

CanonicalID itself. But I don't really care...

Markus

On 8/24/07, Drummond Reed <> wrote:

>

> Les, this requires that each CID being a direct child of the parent CID.

> That's fine if we decide to require that. What we discussed on the call is

> an equally veriable but more flexible rule where each CID must consist of

> valid subsegments from all of its parents.

>

> For example, if @cordance has cid = @!1 but also has LocalID !2 and !3,

> and

> @cordance*drummond has LocalID !4, then any of the following three

> identifiers would be verifiable CanonicalIDs for @cordance*drummond:

>

>         @!1!4

>         @!2!4

>         @!3!4

>

> I'd call this approach "family descendants" and the other
approach "direct

> descendants". The only reason I suggest considering family
descendants is

> that it provides more flexibility in the assignment of CanonicalIDs at

> lower

> levels in the resolution chain. OTOH, if we want to be more restrictive

> and

> require direct descendants, that's fine too (I'm pretty sure they would be

> easier and faster to verify).

>

> How do others feel?

>

> =Drummond

>

> > -----Original Message-----

> > From: Chasen, Les [mailto:]

> > Sent: Friday, August 24, 2007 4:26 PM

> > To: Drummond Reed; 

> > Subject: RE: [xri] Minutes: Special XRI TC Telecon Noon PT Friday

> 2007-08-

> > 24

> >

> > We also got sidetracked into a conversation on CID verification that
I

> > think will need to get re-visited.  Drummond explained how it is

> > possible for CID verification to pass if a parent XRD does not
contain a

> > CID while the child does.  The exact scenario discussed was

> > @cordance*Drummond*home where @cordance and *home have CIDs but

> > *Drummond does not ... but cid verification still passes.

> >

> > I think this is wrong and against the original intent of cid

> > verification.  We MUST verify that every XRD in a hierarchical
chain

> > verify with the parent XRD.  This means that every XRD must have
a CID

> > and each CID must contain the parent node in it's fully qualified
CID.

> > So if @cordance has cid = @!1 then *Drummond must have a CID that
begins

> > with @!1.  If we assume *drummond's cid is @!1!2 then *home
needs to

> > have a cid that starts with @!1!2.

> >

> > contact: =les

> > sip: =les/(+phone)

> > chat: =les/skype/chat

> >

> >

> >

> > > -----Original Message-----

> > > From: Drummond Reed [mailto:]

> > > Sent: Friday, August 24, 2007 6:12 PM

> > > To: 

> > > Subject: [xri] Minutes: Special XRI TC Telecon Noon PT Friday

> > 2007-08-24

> > >

> > > Following are the minutes of the special unofficial XRI TC
telecon

> > held

> > > at:

> > >

> > > Date:  Friday, 24 August 2007 USA

> > > Time:  12:00PM - 1:00PM Pacific Time

> > >

> > > TO ACCESS THE AUDIO CONFERENCE:

> > >     Dial In Number: 571-434-5750

> > >     Conference ID: 5474

> > >

> > > ATTENDING

> > >

> > > Wil Tan

> > > Markus Sabadello

> > > Les Chasen

> > > Drummond Reed

> > >

> > >

> > > The subject of the call was the current synonym semantics
proposal at:

> > >

> > >     http://wiki.oasis-open.org/xri/XriCd02/SynonymSemantics

> > >

> > > Key points from the call:

> > >

> > > * We briefly discussed Bill Barnhill's proposal to the list but
the

> > > conclusion was that: a) we don't want to change the definitions
of

> > > LocalID,

> > > CanonicalID, and Ref due both to the installed base and to the
fact

> > that

> > > there is (now) relatively strong consensus on the use of these
synonym

> > > elements (see below), and b) adding attributes to a single
synonym

> > element

> > > does not enable control at the XML schema level of cardinality,
which

> > is

> > > important for elements such as CanonicalID (and the proposed
UseCID).

> > >

> > > * We had a long discussion about the underlying needs for
applications

> > to

> > > store a persistent identifier for a resource, touching upon many

> > different

> > > potential scenerios: when they are constrained (by schema or
data

> > store)

> > > to

> > > having only one, when they can keep alternates, when they need
to know

> > > equivalence relationships, etc.

> > >

> > > * We also discussed the use cases that require a target
resources to

> > > merge,

> > > migrate, or simply associate identifiers, such as an individual
moving

> > > from

> > > one community to another or two businesses merging.

> > >

> > > * We established that have consensus about the purpose and uses
of

> > Ref.

> > > The

> > > only inputs that determined whether a Ref is following or not
are the

> > > QXRI,

> > > the refs= parameter, and the service endpoint selection
parameters.

> > The

> > > cid

> > > parameter will NOT affect affecting Ref processing.

> > >

> > > * We also have consensus that EquivID should have zero-or-more

> > > cardinality,

> > > is used to express equivalence relationships between
identifiers, and

> > can

> > > be

> > > used in conjunction with the priority attribute to express the

> > priority of

> > > such equivalence assertions.

> > >

> > > * Where we do not have consensus yet is if or how an XRD should
enable

> > > expression of a "stronger than equivalence" mapping
relationship

> > between

> > > two

> > > identifiers. Such a relationship might be called
"directional",

> > > "precessor/successor", "migration",
"replacement", "preference",

> > > "redirect",

> > > or many other terms.

> > >

> > > * Les proposed that we define a PreferredID element for this
purpose

> > with

> > > roughly the following definition: "The purpose of this tag
is to

> > express

> > > the

> > > preferred identifier for the target resource if that preferred

> > identifier

> > > is

> > > not the QXRI or CanonicalID. It is recommended that applications

> > retain

> > > this

> > > identifier in their local account for future reference to this

> > resource."

> > >

> > > * Drummond proposed that the core underlying motivation is to
support

> > the

> > > need of XRD authors to inform consuming applications that they
should

> > > associate two primary global foreign keys for a resource.

> > >

> > > * After 2.5 hours of discussion, we agreed that next step is for
all

> > TC

> > > members who have specific views on this issue to post their
views to

> > the

> > > SynonymSemantics page of the wiki.

> > >

> > > * There will be another followup call on this topic on the same

> > telecon

> > > number at 8AM PT/11AM ET Monday August 27th.

> > >

> > > =Drummond

> > >

> > >

>

>

>