"Privacy is not about secrecy. It's about context, control, choice, and respect." (UMA webinar, after Bob Blakley)

Abstract

This document explores legal issues raised by the act of using User-Managed Access (UMA) to authorize another party to get web resource access.

Status

This document is a product of the User-Managed Access Work Group. It 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

• Eve Maler
• Tom Smedinghoff ??

Intellectual Property Notice

The User-Managed Access Work Group operates under Kantara IPR Policy - Option Patent & Copyright: Reciprocal Royalty Free with Opt-Out to Reasonable And Non discriminatory (RAND) and the publication of this document is governed by the policies outlined in this option.

Table of Contents

Introduction

User-Managed Access (UMA) gives a web user a unified control point for authorizing who and what can get access to his or her online personal data (such as identity attributes), content (such as photos), and web-based services (such as viewing and creating Twitter-style status updates), no matter where all those things "live" on the web. Further, UMA allows the user to make demands of the other side in order to test their suitability for receiving authorization. These demands can include requests for information (such as "Who are you?") and promises (such as "Do you agree to these Non-Disclosure Agreement terms?").

This is a tall order, with implications that go beyond cryptography and security, and web protocols and technology, into the realm of agreements and liability. UMA targets end-user convenience and development simplicity as goals. But it also seeks enforceability of authorization agreements, in order to make the act of granting data and service access truly informed, uncoerced, and meaningful – no longer a matter of mere passive consent but rather a step that more fully empowers ordinary web users.

For all these reasons, the UMA Work Group is exploring issues related to authorization policy, contracts, liability, and enforceability that arise among the various actors in UMA interactions. (Note: This document is intended to be accessible to readers, even relatively nontechnical ones, who have expertise in these areas, and we welcome suggestions for improvement.)

Starter Scenarios

Let's imagine a web user, Alice Adams, who doesn't mind sharing her personal travel information with the right sources as long as the process of sharing is convenient (e.g., no requirements to alert authorized recipients every time a new trip gets booked); her expectations for the uses of that information are met (e.g., she's not worried about recipients divulging to the whole world that her house is going to be empty); and she feels "in control" of what's allowed and not allowed (e.g., she can get an at-a-glance view of who's seeing what).

She uses a website called TravelIt.com (think TripIt) to store all of her travel itineraries. Since it's the nature of travel information to change frequently, she wants to be sure that her good friend Bob Baker always has the latest version so he can pick her up from the airport on time and make sure her cat is fed while she's away; he likes to use Schedewl.com (think Google Calendar) for subscribing to TravelIt. She would also like her social travel site Airplanr.com (think Dopplr) to pick up her itineraries automatically and make them available to friends who are on that system.

Because Alice is a frequent and seasoned traveler, she's interested in entertaining discount offers from travelogue company FrodoReviews.com (think Frommer's) for making her itineraries available to them for survey purposes.

To this picture, UMA adds the possibility of a new kind of web-based application: a kind of "traffic cop" for overseeing all these instances of travel itinerary sharing, which will help Alice manage her digital footprint. We'll call this site CopMonkey.com.

UMA overview and terminology

As hinted in the introduction, UMA involves four main players:

• Alice is an authorizing user: a web user who gets to be in charge of authorizing access to his or her "stuff" on the web (known as protected resources).
• The TravelIt application acts as a host: one of possibly many websites where Alice's resources are stored and managed in various fashions.
• The Schedewl, Airplanr, and FrodoReviews applications act as requesters: web-based applications that seek access to the authorizing user's resources. Access may mean more than just downloading or viewing, for example adding more "stuff" to be stored, or manipulating or transforming it in some other way.
• The CopMonkey application acts as an authorization manager or AM: a unified web-based control point that makes it easy for Alice to set up protections for all those resources at their various hosts, and to control and track access to them by requesters.

So far, this description relates only to the UMA web protocol itself. These four players are commonly referred to as "endpoints" in discussions of computing protocols (or sometimes as "entities" or "parties", but we'll avoid these in order to avoid confusion with the legal connotations of these words). Protocols define rules, and you can think of each these players as serving in a unique role with certain expectations and responsibilities, as if the rules were about soccer and governed the allowed actions of goalkeepers versus outfielders.

You might be asking, Where did Bob go? Recall that the authorizing user can make demands of the other side to judge their suitability for access. We must ask: What is the nature of the "other side"? The authorizing user is flesh-and-blood, but the AM, host, and requester endpoints are just tools. They are implemented in software, and the software is deployed in the form of networked applications and services. A tool can't be responsible for the consequences of accessing an authorizing user's "stuff". For this reason, we introduce another important player that's not strictly part of the UMA protocol:

• In our examples, Bob and the companies that run Airplanr and FrodoReviews are requesting parties: legal persons (such as corporations) and real human beings (other than Alice herself) who use a requester endpoint to seek authorized access to some protected resource.

We'll explore this most complex set of players more in a moment.

Finally, we need to ask: What is the nature of these "demands" and their responses? Since we're talking about web interactions, the authorizing user isn't exactly sitting across a table from the requesting party (or their legal or business representative) in real time, pestering them with questions. Rather, the authorizing user can, at leisure, configure the AM with policies that constrain the conditions for access by others. When a requester endpoint comes calling, the AM may ask it to convey the following:

• A set of claims: one or more affirmative or promissory statements about the requesting party that are intended to satisfy some policy Alice has configured into her AM.

Now we have enough language to begin discussing potential access authorization agreements and liability that may obtain between two parties (yes, in the legal sense) interacting in an UMA environment: the authorizing user and the requesting party.

Person-to-service access: a walkthrough

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Person-to-person access: a walkthrough

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TBS

Here are the choices for requesting party:

1. Requesting party is a natural person, that is, a human being
   
   
   1. That person is the same as the authorizing user (person-to-self sharing)
      
      
      1. That person operates the service that runs the requester endpoint ("Alice authorizes herself to see her geolocation at a host, using her own homegrown requester app that logs travel")
         
         
      2. That person uses some third-party service that runs the requester endpoint as an intermediary, with which he/she has a separate agreement for terms of use ("Alice authorizes herself to subscribe to her calendar at host Googol Cal, using the popular Schedewl online app"): A
         
         
   2. That person is different from the authorizing user (person-to-person sharing)
      
      
      1. That person operates the service that runs the requester endpoint ("Alice authorizes Bob to see her geolocation at a host, using his own homegrown requester app that tracks her travel")
         
         
      2. That person uses some third-party service that runs the requester endpoint as an intermediary, with which he/she has a separate agreement for terms of use ("Alice authorizes Bob to subscribe to her calendar at a host, using the popular Schedewl online app where he has an account"): X
         
         
2. Requesting party is a legal person, such as a company (person-to-service sharing)
   
   
   1. That legal person operates the service that runs the requester endpoint on its own behalf ("Alice authorizes the survey company DataSuck to pull copies of her self-asserted demographic data on an ongoing basis")
      
      
   2. That legal person operates the service that runs the requester endpoint on the behalf of some person, with whom it has a separate agreement for terms of use
      
      
      1. That person is the same as the authorizing user ("Alice authorizes Schedewl to subscribe to her calendar at host Googol Cal, acting on behalf of her own account at Schedewl"): B
         
         
      2. That person is different from the authorizing user ("Alice authorizes Schedewl to subscribe to her calendar at host Googol Cal, acting on behalf of Bob's account at Schedewl"): Y

Note that 1.a.ii and 2.b.i are protocol alternatives (denoted with A and B) for what could be the same basic kind of authorized access. In the first, the authorizing user and the requesting party are both Alice, and if any claims are required she supplies them to herself, but she has chosen to use some service run by a third party to manage requests for access. In the second, Alice uses the same such service but expects it to speak for itself in responding to demands for claims (possibly providing claims about her in the process).

Similarly, 1.b.ii and 2.b.ii are protocol alternatives (denoted with X and Y). In the first, Alice authorizes Bob for access, and Bob happens to use an intermediary service to help manage his requests. In the second, Bob uses the same such service but expects it to speak for itself in responding to demands for claims (again, possibly providing claims about him in the process).

We are actively researching this issue. See the notes from UMA telecon 2010-03-18 for discussion about the impact of choosing one alternative over another.

The nature of claims

A claim may be affirmative, representing a statement of fact (as asserted by the requesting or another claim issuer); or promissory, a promise (as asserted by the requesting party specifically to the authorizing user). A statement of fact might be "The requesting party is over 18 years of age." A promise might be "The requesting party will adhere to the specific Creative Commons licensing terms indicated by the AM." There are technical dimensions to expressing and conveying claims, but since UMA strives to provide enforceability of resource-access agreements, there may also be legal dimensions.

In cases where a claim constitutes acceptance of an access-sharing contract offer made by the authorizing user (as presented by the AM as his or her agent in requiring the claim), the authorizing user and requesting party are the parties to the contract, and all other legal or natural persons running UMA-related services involved in managing such access are intermediaries that are not party to the contract (though they might end up being third-party beneficiaries in some cases).

Where the primary resource user and the authoring user differ, there is likely to be an interaction (invisible to UMA) at the host service that allows (or forces) the primary resource user to designate an authorizing user, and an agreement that the authorizing user acts as the primary resource user's agent or guardian or similar.

Mapping requesting parties to profiles for getting access tokens

We suspect that certain sharing patterns lend themselves to choosing different profiles for UMA's step 2 (getting a token).

• Person-to-self sharing could possibly use any profile of the WRAP user delegation type, since the same person would have an account on the requester and AM sides.
• Person-to-service sharing could possibly use any profile of the WRAP autonomous client type, since the service itself operates the WRAP client that is embedded in the UMA requester.
• Person-to-person sharing could also possibly use any profile of the WRAP autonomous client type, since everyone and everything on the requesting side is "autonomous" with respect to the authorizing side. However, an entirely new set of profiles might be appropriate instead, to take into account the requesting person's personal involvement in providing claims, confirming agreements, etc.

We are actively researching this issue.

Change History