Abstract

This document is a product of the User-Managed Access Work Group. It records the scenarios and use cases governing the development of the User-Managed Access protocol and guiding associated implementations and deployments.

Status

This document is currently under active development. Its latest version can always be found here. See the Change History at the end of this document for its revision number.

Editors
Intellectual Property Notice

The User-Managed Access Work Group operates under Option Liberty and the publication of this document is governed by the policies outlined in this option.


Table of Contents


Introduction and Instructions

This document is a product of the User-Managed Access Work Group. It records the scenarios and use cases governing the development of the User-Managed Access protocol and guiding associated implementations and deployments, and outlines technical issues raised thereby.

Please use the scenario template near the end of this document in adding new scenarios and subordinate use cases. Change the status keyword in each scenario and use case title as appropriate, linking to the meeting minutes page explaining the status change:

Edit the descriptions of technical issues and scope questions to reflect (or point to) group decisions about how to handle them.


Scenario: unique-title (Pending)

Submitted by: participant-name

(Provide description of the scenario with all nontechnical particulars, noting requirements, constraints, and other observations. Avoid diagrams.)

Use Case: unique-title (Pending)

Submitted by: participant-name

(Provide description of a use case matching this scenario with all technical particulars, such as the topological configuration of protocol endpoint entities, potential wireframes, listings and assessments of technical issues, and anything else helpful.)


Issues

Following are discussions of technical issues raised by one or more scenarios and use cases. Acceptance of a scenario or use case will imply agreeing to develop a satisfactory solution to applicable issues.

Issue: Policies Specific to the Web Resource Type

Related to: calendar scenario, location scenario

There is a potential need to restrict, anonymize, blur, or otherwise transform a shared resource, possibly based on the unique characteristics of its content type.

With respect to calendar resources, the premier calendar format standard already accounts for a blurring of data details by providing a "free/busy" option in addition to a full-data option. It feels like it should be out of scope to solve for filtering the calendar data cleverly (beyond the format's natural capabilities) to hide Alice's destination, hotel, etc. (though generic solutions such as making events taggable, and then filtering on the tags in a relationship manager interface, come to mind). An "identity oracle" approach (filtering the data into a completely different type) might be necessary if what Alice is trying to convey is simply "don't deliver my newspaper on these days" vs. "here's all of my travel information".

In the Controlling Two-Way Sharing of Location Information scenario, note that FireEagle allows a user to choose to share locations only at the city level, and this level happens to be chosen for the connection that authorizes Dopplr to read the FireEagle location (a different level can be chosen for each application that reads location from FireEagle). As it happens, Dopplr does not offer the same policy capability. Without having to teach UMA generically about all the possible policy options specific to all the kinds of information in the world, is it possible for each Host to teach each AM about the policy options it offers, in some way that lets the the relationship manager application surrounding the AM present user interface options to see and select these policies? Seeing may have less protocol impact than selecting, and seems to be a minimum value-add if the goal is to allow OAuth users to get a global view.

Some data-usage policies and terms may possibly have an interaction with some resource types, such as requiring recipients to discard volatile data after a period dictated by the data's type.

It has been observed that if fine-grained calendar filtering were a solved problem, different calendar sites could be shared with different friends as a way of managing minimal disclosure through indirection.

Issue: Authorization Manager Endpoint Discovery

Related to: calendar scenario, location scenario

The mockups linked in the calendar scenario imagine that the user's authorization manager endpoint (what we imagine Alice will perceive as the name of her relationship management service) will be handled as if it were an OpenID, with introductions to popular relationship manager services offered in an array by potential UMA Hosts much in the way that the RPX solution presents options. (The user always has the ability to self-host an authorization manager endpoint, similarly to self-hosting an OpenID provider – and they might even be colocated.)

Issue: Handling the Resource URL and Provisioning It to the Consumer Site

Related to: calendar scenario, location scenario

The mockups linked in the calendar scenario imagine the simplest possible situation: The Consumer site literally asks for exactly the kind of information it needs, and the user copies and pastes a URL into a field.

This is how calendar feeds, photo streams, RSS feeds, and other such resources are shared today; it works but we need to consider its scalability to arbitrary types of information. There are several challenges here: The Consumer's ability to handle the information, its way of expressing the desire/need for the correct information, and the user's (or user agent's) ability to provide it in a convenient and correct fashion.

In addition, the relationship manager interface is shown having some knowledge of that resource as a unique object. We need to consider how to let the AM and SP communicate about this information appropriately.

In the case of the photo set scenario, note that in OAuth usage today, the resource-based interaction is often accomplished silently from the user's perspective: the desired combinatorial effect simply "happens" as if the feature that was "outsourced" to a third-party app were native. Perhaps this is possible in the UMA approach.

Issue: Processes By Which Consumers Meet the User's Data-Sharing Terms

Related to: calendar scenario, location scenario

Some of the vendors mentioned in the calendar scenario are big companies; can standard (and machine-readable) data-sharing contract terms be developed and pre-negotiated such that, when such contracts are offered by an individual, they are likely to be accepted and met? Small companies such as a modest medical practice may need a human-accessible interface and the option of an "I Agree" button so that the person manually fielding Alice's offer of data can complete the transaction.

It may be necessary for us to consider "partial measures" in the V1 UMA effort to improve adoption. Some such measures are: terms that can be passively accepted ("I Agree") rather than terms that require positive demonstration of intent (such as payment receipts); policies that don't require explicit agreement on the part of the recipient but are somehow attached to the data supplied ("sticky policies"); and policies about which the recipient is merely informed rather than asked to agree with.


Change History