XDI TC Notes

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

Date: Tuesday, 22 November 2016 USA
Time: 9:00AM - 10:00AM Pacific Time (17:00-18:30 UTC)

The TC operates under a standing rule approved 17 July 2008 under which the TC does not hold regular official meetings and conducts all business by electronic ballot only. Unofficial weekly meetings are held to enable discussion among members but no business is conducted nor actions taken.

ATTENDING

Markus Sabadello
Drummond Reed
Joseph Boyle

REGRETS

Les Chasen

NOTES

XDI Message Templates

Markus has done some work on message templates (as specified in the XDI Messaging Spec Working Draft 05):

http://xdi.org/xdi-spec-docbook/xdi/xdi-messaging-1.0/xdi-messaging-1.0-wd05.xml

Message templates are similar to link contract templates. Messages can be created from message templates, just like link contracts can be created from link contract templates.

Example message template:

(#register{$msg}$do/$set){(#name)}/$ref/{(#number)}

(#register{$msg}$do/$set){(#number)}/$is$ref/{(#name)}

(#register{$msg}$do/$set){#name}/$ref/{#number}

(#register{$msg}$do/$set){(#number)}<$digest><$secret><$token>/{&}/{<#password>}

Example $send operation to create and send a message based on the above message template:

=sender[$msg]@~0$do/$send/#register{$msg}

=sender[$msg]@~0$do$send{$from}/$is/=!:uuid:1111

=sender[$msg]@~0$do$send{$to}/$is/=!:uuid:2222

=sender[$msg]@~0$do$send{#name}/$is/=markus

=sender[$msg]@~0$do$send{#number}/$is/=!:uuid:3333

=sender[$msg]@~0$do$send{<#password>}/&/"s3cr3t"

Example message instantiated by the above $send operation:

=!:uuid:1111[$msg]@~1/$is#/#register{$msg}

=!:uuid:1111[$msg]@~1/$from/(=!:uuid:1111)

=!:uuid:1111[$msg]@~1/$to/(=!:uuid:2222)

(=!:uuid:1111[$msg]@~1$do/$set)(=markus)/$ref/(=!:uuid:3333)

(=!:uuid:1111[$msg]@~1$do/$set)(=!:uuid:3333)/$is$ref/(=markus)

(=!:uuid:1111[$msg]@~1$do/$set)=markus/$ref/=!:uuid:3333

(=!:uuid:1111[$msg]@~1$do/$set)(=!:uuid:3333)<$digest><$secret><$token>/&/"s3cr3t"

We discussed that message templates are useful to simplify sending common messages, by defining a pattern in the message template, and then only setting variable values for the $send operation.

XDI Passenger Name Record Demo

Markus has prepared an XDI demo for the "Rebooting the Web of Trust (RWoT) - Europe" meetup that will take place in Paris this week:

https://www.meetup.com/Rebooting-the-Web-of-Trust-RWoT-Europe/events/235396181/

This demo involves a train passenger storing their ticket in a personal cloud. The ticket can then be viewed and updated by railway companies, using XDI link contracts.

A screencast for the demo as well some technical details can be found here:

https://vimeo.com/191811593

https://github.com/projectdanube/aeternam-xdi-webshop/

XDI Dictionaries

Drummond proposes to discuss how XDI dictionaries may represent an opportunity to begin advancing XDI adoption due to the particular semantics sharing problem that they can solve—potentially even for users of RDF and JSON-LD.

Drummond shared a thesis that data interoperability, after it has moved into the “JSON age” (i.e., after the age of XML and XML schemas), has one of three choices:

Use plain JSON trees
Use “flat” RDF graphs
Use XDI semantic trees

The challenge with plain JSON trees is that this is primarily used for data in already established domains. The challenge with RDF ontologies is that they have a natural limitation due to the flat graph structure.

Markus shared his view that he has felt that XDI dictionaries could be a powerful tool for mapping data across different schemas and domains, especially in combination with XDI connector architecture that has been built successfully e.g. for accessing data in Facebook, Personal.com, Meeco, CozyCloud.

Markus felt that having contextual data definitions and instance mappings makes sense and can indeed solve data sharing problems which are very difficult to solve with plain JSON or RDF.

Markus also made the point that it’s not just identifiers that need “self-sovereignty”, but also data definitions. If someone else controls the schema/ontology of what an individual can express, then the data is not in fact self-sovereign. Many data schemas have cultural or political bias. XDI dictionaries can help remove that bias and yet still enable interoperability.

This reopened discussion of a community dictionary service that would meet the public need for interoperability.

NEXT REGULAR CALL

The next call will be the following week at the usual time (Tuesday 9AM PT). The link to where agenda items can be posted for the next meeting is: https://docs.google.com/document/d/19oDl0lbb56Grehx2a5flZnhrgnua5l8cVvC_dJ8fTXk/edit?usp=sharing

xdi message