Difference between revisions of "PDS Architecture"

Revision as of 18:08, 10 October 2010

What is sometimes called a personal data store lies at the heart of a Personal Data Service (PDS). This page describes both the PDS and the personal and 3rd party managed data stores that it manages.

Introduction

A PDS provides a central point of control for information about a person, their lives, friends, interests, affiliations and so on. It provides a web portal and a dashboard of the user’s data. It includes the ability update self-asserted data and a way to manage authorizations and set policies under which 3rd parties gain access to portion of the user’s information. It implements a Discovery API that allows you to be discoverable by other people, organizations, apps and exchanges whose inquiries that meet criteria you specify

A personal data store is a data service where self-asserted information about the user is stored and protected. A managed data store is a data service managed by a third party and providing information about the user.

A PDS enables the user to participate as a peer within what we anticipate will be a distributed personal data ecosystem of interoperable PDSes developed and operated by a wide variety of organizations. We share a vision with other open source projects of an internetwork of PDSes that can freely exchange information of a wide variety of types. One person will have links to data objects stored in a friend's PDS. These pointers, taken together, form the social graph that is physically distributed across the PDSes.

A PDS centralizes control by providing the person with a dashboard, but it does not centralize the location of the data. Quite the opposite. At the heart of the PDS concept is the idea of a distributed architecture. Theoretically every person could run their own PDS in their home in or in the cloud. Alternatively, a PDS may be operated by an organization; hopefully an organization that acts as an agent of the individual.

PDS Apps

PDS

Information from a variety of data sources (e.g. social networks, telco and health data sources) are virtually integrated by the PDS and presented in a "dashboard" application in a browser or in desktop and mobile clients. The PDS gives you control over your own information by allowing you to share selected subsets of it with other people and organizations that you trust.

A PDS:

• Is a service that enables the user to participate as a peer within a distributed personal data ecosystem
• Provides a web portal that provides a dashboard view of the user’s data, the ability update self-asserted data, and a way to manage authorizations (e.g. using something like an UMA Authorization Manager) and set policies under which 3rd parties gain access to portion of the user’s information
• Implements a Discovery API that allows you to be discoverable by other people, organizations, apps and exchanges whose inquiries that meet criteria you specify
• Provides an identity provider (IdP) endpoint (e.g. OpenID OP)
• Implements two factor authentication
• Provides a run-time environment for apps that run within the PDA itself
• Decrypts data from your PDS (using a locally stored key) to allow it to be managed in the PDA's "dashboard" UI. Attribute data stored locally on the PDA are encrypted by the PDS Client using an internally managed key prior to transmission to the PDS. Thus data attribute values on the PDS are blinded from the service operator offering/hosting the PDS.
• Manages access by external apps (aka service providers) to your data that is stored locally as well data stored in PDSes managed by external organizations

Personal data service

• Provides a personal data abstraction layer mapping internal and external data sources into a consistent data model based around notions of personas
• Manages a set of your personas (e.g. Work, Home & Friends, Citizen, Health, Anonymous)
• Provides an encrypted "lock box" in the cloud such that certain internally stored data in the PDS (e.g. your persona definitions) cannot be read by the PDS's operator
• Backs up personal data stored on your desktop and mobile devices
• Synchronizes personal data to other devices and computers owned by the person using a variety of network protocols.
• Links information from your personas to accounts (profiles) that you have at services providers, websites, social networking sites, etc. and over which you share joint control and rights
• Links information from your personas with the personas of your friend's and colleague's PDSes

Managed data service

• Gives you control over your information stored in hundreds of external silos
• Provides a personal data abstraction layer mapping internal and external data sources into a consistent data model based around notions of personas

Contextualized data model

At the heart of the personal data store and managed data stores are a set of data objects called contexts, each of which holds a set of attributes. These contexts are usually rendered as digital cards in a user interface. A context/card could hold the attributes of a person's driver's license, home address, credit card. They might simply hold a verified assertion that a person is over 21 years of age. Contexts may also be about friends and colleagues, not just about you.

We all play different roles and share different sub-sets of our social graph and attributes depending on who we're interacting with. That's what humans do. For this reason a single person is represented as a set of partial identities that are used in different contexts.

The user can group a set of these partial identities into something called a persona. For example the user could group together a home address card, an AMEX credit card, a proof of age-over-21 and a card holding a set of "shopping friends" into an "eCommerce" persona. This is done by tagging each of these cards with the "eCommerce" label. When the user goes to a new eCommerce site, it can "project" (either by form filling or something more sophisticated!) the minimal set of required attributes from these "eCommerce" cards to the site without tedious data entry.

What's more, if the user desires, the user can give a semi-permanent (revocable) permission to the relying site, app or system to be able to access an approved set of attributes from the user's PDS whenever needed. The user can basically send a "pointer" to these cards to the relying site. The relying site can de-reference the pointer and read (and in some cases update) selected attributes.

Active Clients

As shown at the top of the diagram above, we are developing native Windows, Mac and mobile active clients for the PDS. These clients have two advantages over the web-based PDA. First, data stored on these devices is entirely under your control without the need to rely on third party hosted services. Second, the client is closely integrated with the browser and other local apps. This allows the client to capture information about you as you browse and can augment your web experience through web augmentation (overlaying context-specific information within your browser) as well as through automatic form filling (e.g. filling in your passwords).

Representing a Person

A natural person is represented in a PDS as a set of containers called contexts each of which holds a partial digital identity called a persona. Each persona instance has a set of attributes and values. Thus one individual (natural person, data subject) is represented as multiple personas each in its own context-container.

The data in these contexts adheres to the Higgins Persona Data Model 2.0, which can be used for storing arbitrary (identity and social networking) data. UDI references are used for representing links between contexts, both inside the PDS 2.0 and to external data stores.

Components

• PDS 2.0: Personal Data Store core service
• PDA: We have not even started developing this component for Higgins 2.0. We developed something similar in Cloud Selector from Higgins 1.1. Similar in that it was a pure web app and that it was a "client" of the core PDS.
• PDS Client 2.0: a library used to access the Personal Data Store 2.0. It is incorporated into the PDS agent as well as PC and mobile PDS clients.
• Authentication Service 2.0: is an OAuth web service that authenticates PDS users and returns an access token that is relied on by the PDS Agent and the PDS Vault.

Data Models

Data models used in Higgins code and services:

• Persona Data Model 2.0
• Higgins Data Model 2.0
• Context Data Model 2.0

IdAS 

The IdAS solution is a testbed for exercising the IdAS Java framework.

• Higgins 1.1: See Higgins 1.1 Plan#IdAS_Solution_1.1
• Higgins 1.0: IdAS Solution 1.0: a basic configuration of the Identity Attribute Service 1.0 (IdAS). IdAS is a java framework that provides a common interface to identity, profile, and relationship data from external data sources (e.g. websites, databases, directories).

XDI4J

XDI4J is a java library for working with XDI.

• Higgins 1.1: XDI4j 1.1