XDI TC Minutes

Following are the minutes of the unofficial telecon of the XDI TC held on:

Date: Friday, 24 April 2015 USA
Time: 09:00AM - 10:30AM Pacific Time

ATTENDING

Phil Windley
Markus Sabadello
Joseph Boyle
Drummond Reed
Les Chasen

NEWS & UPDATES

“Phaidra” Digital Archiving at University of Vienna

Markus met with people from the IT department at the University of Vienna, who had reached out on the OpenXRI mailing list to explore the use of XRI/XDI technology for their digital archiving system “Phaidra”: http://phaidra.org/

Next steps are for the “Phaidra” team to set up an XDI server and evaluate it for their purposes.

PRESENTATIONS/DISCUSSIONS

Namespace Architecture (Local Name Syntax)

At the F2F meeting at Internet Identity Workshop in Mountain View, CA, the TC members present discussed but did not reach consensus on the local name syntax issue. Drummond has done a writeup on this issue to help us move to closure:

https://wiki.oasis-open.org/xdi/LocalNameSyntax (now contains just a recommendation)

https://wiki.oasis-open.org/xdi/NamespaceArchitecture (full writeup)

We talked about the proposed _ “relativity symbol” and noted that DNS does not have an equivalent concept, since in DNS names are relative at all levels except the very top, whereas in XDI identifiers at any level except the top may be either absolute or relative to the parent context (like DNS, identifies at the very top level must be absolute).

Joseph asked whether the _ underscore character would be used exclusively for the relativity symbol, or whether it was also allowed as a character within an identifier. This would make _ the only character in XDI syntax that serves both a syntactical function and can also be used as a regular character inside an identifier. Drummond and Phil felt this should be possible since there is no syntactic conflict. Phil argued that _ was very common inside identifiers of various technologies, whereas e.g. ! was rare. But because it was not reserved just for usage as an XDI delimiter, Phil suggested we the term “relative prefix” (short for “relative identifier prefix”) instead of “relativity symbol”.

We then looked at absolute and relative identifier sequences and why they were an interesting feature of XDI identifiers because again there is no equivalent in DNS.

We also discussed that with the introduction of the relative prefix, there would only two uses of ( ) parentheses in XDI:

Peer/inner roots
Absolute URI references.

This is a good thing since it simplifies syntax and will reduce confusion about the use of parentheses.

We agreed that for all these reasons we finally had consensus on this issue.

#CONSENSUS: We will adopt the proposal documented on https://wiki.oasis-open.org/xdi/LocalNameSyntax and https://wiki.oasis-open.org/xdi/NamespaceArchitecture for using underscore as the XDI relative identifier prefix.

#ACTION ITEM: XDI CORE EDITORS to update the ABNF to reflect this.

We discussed whether URIs or IRIs should be used in XDI syntax. The IRI specification (RFC 3987) defines a mechanism for transforming IRIs to URIs. Drummond felt there was a tradeoff: If XDI used IRIs, that might be more readable and preferable from an internationalization perspective. If XDI used URIs, certain functionality such as normalization and comparison would be easier. Joseph pointed us to the RDF 1.1 Concepts and Abstract Syntax, and in particular section 3.2. Joseph recommended that we follow the RDF example, which uses IRIs, and defines comparison and normalization rules.

#CONSENSUS: We will follow the precedent of RDF and use IRIs uniformly through the XDI 1.0 specifications.

Finally, we considered whether we should use the terms “XDI names” and “XDI numbers” for mutable/immutable identifiers. Joseph and Les felt this might lead to confusion, considering that immutable identifiers are not necessarily numbers.

#CONSENSUS: We will not use the term “XDI number” in XDI Core, only the term “XDI name”, and when necessary refer to “mutable XDI name” and “immutable XDI name”.

XDI Encryption

Markus has been experimenting with encryption of XDI subgraphs:

https://server.xdi2.org/XDIEncrypter

This appears to have many parallels with signing:

https://server.xdi2.org/XDISigner

We did not discuss this topic, realizing that input from more TC members would be desirable here.

NEXT CALL

The next call is next week at the regular time.

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