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<!DOCTYPE html>
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<title>Verifiable Credentials Data Model v2.0</title>
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<body>
<section id='abstract'>
<p>
[=Credentials=] are integral to our daily lives: driver's licenses confirm
our capability to operate motor vehicles; university degrees assert our level
of education; and government-issued passports attest to our citizenship when
traveling between countries. This specification provides a mechanism for
expressing these sorts of [=credentials=] on the Web in a way that is
cryptographically secure, privacy respecting, and machine verifiable. These
[=credentials=] provide benefits to us when used in the physical world, but
their use on the Web continues to be elusive.
</p>
</section>
<section id='sotd'>
<p>
The Working Group is actively seeking implementation feedback for this
specification. In order to exit the Candidate Recommendation phase, the
Working Group has set the requirement of at least two independent
implementations for each mandatory feature in the specification. Please see
the <a href="https://w3c.github.io/vc-data-model-2.0-test-suite/">
implementation report</a> for more details.
</p>
<p class="atrisk issue"
title="Features with less than two independent implementations">
Any feature with less than two independent implementations in the
<a href="https://w3c.github.io/vc-data-model-2.0-test-suite/">
implementation report</a> is an "at risk" feature and might be
removed before the transition to W3C Proposed Recommendation.
</p>
<p>
Comments regarding this specification are welcome at any time.
Please file issues directly on
<a href="https://github.com/w3c/vc-data-model/issues/">GitHub</a>,
or send them to
<a href="mailto:[email protected]">[email protected]</a>
if that is not possible.
(<a href="mailto:[email protected]?subject=subscribe">subscribe</a>,
<a href="https://lists.w3.org/Archives/Public/public-vc-comments/">archives</a>).
</p>
</section>
<section class="informative">
<h2>Introduction</h2>
<p>
[=Credentials=] are integral to our daily lives: driver's licenses confirm
our capability to operate motor vehicles; university degrees assert our level
of education; and government-issued passports attest to our citizenship when
traveling between countries. This specification provides a mechanism for
expressing these sorts of [=credentials=] on the Web in a way that is
cryptographically secure, privacy respecting, and machine verifiable. These
[=credentials=] provide benefits to us when used in the physical world, but
their use on the Web continues to be elusive.
</p>
<p>
It is currently difficult to express educational qualifications, healthcare
data, financial account details, and other third-party-[=verified=]
personal information in a machine readable way on the Web. The challenge of
expressing digital [=credentials=] on the Web hinders our ability to receive
the same benefits from them that physical [=credentials=] provide in the
real world.
</p>
<p>
For those unfamiliar with the concepts related to
[=verifiable credentials=], the following sections provide an overview of:
</p>
<ul>
<li>
The components that constitute a [=verifiable credential=]
</li>
<li>
The components that constitute a [=verifiable presentation=]
</li>
<li>
An ecosystem where [=verifiable credentials=]
and [=verifiable presentations=] are useful
</li>
</ul>
<p>
The use cases and requirements that informed this specification can be found
in [[[VC-USE-CASES]]] [[?VC-USE-CASES]].
</p>
<section class="informative">
<h3>What is a Verifiable Credential?</h3>
<p>
In the physical world, a [=credential=] might consist of:
</p>
<ul>
<li>
Information related to identifying the [=subject=] of the [=credential=]
(for example, a photo, name, or identification number)
</li>
<li>
Information related to the issuing authority (for example, a city government,
national agency, or certification body)
</li>
<li>
Information related to the type of [=credential=] (for example, a
Dutch passport, an American driving license, or a health insurance card)
</li>
<li>
Information related to specific properties asserted by
the issuing authority about the [=subject=] (for example, nationality,
date of birth, or the classes of vehicle they're qualified to drive)
</li>
<li>
Evidence by which a [=subject=] was demonstrated to have satisfied the
qualifications required for issuance of the [=credential=] (for example,
a measurement, proof of citizenship, or test result)
</li>
<li>
Information related to constraints on the credential (for example,
validity period, or terms of use).
</li>
</ul>
<p>
A [=verifiable credential=] can represent all the same information that a
physical [=credential=] represents. Adding technologies such as
digital signatures can make [=verifiable credentials=] more tamper-evident and
trustworthy than their physical counterparts.
</p>
<p>
[=Holders=] of [=verifiable credentials=] can generate
[=verifiable presentations=] and then share these
[=verifiable presentations=] with [=verifiers=] to prove they possess
[=verifiable credentials=] with specific characteristics.
</p>
<p>
Both [=verifiable credentials=] and [=verifiable presentations=] can be
transmitted rapidly, making them more convenient than their physical
counterparts when establishing trust at a distance.
</p>
<p>
While this specification attempts to improve the ease of expressing digital
[=credentials=], it also aims to balance this goal with several
privacy-preserving goals. The persistence of digital information, and the ease
with which disparate sources of digital data can be collected and correlated,
comprise a privacy concern that the use of [=verifiable=] and easily
machine-readable [=credentials=] threatens to make worse. This document
outlines and attempts to address several of these issues in Section
[[[#privacy-considerations]]]. Examples of how to use this data model
using privacy-enhancing technologies, such as zero-knowledge proofs, are also
provided throughout this document.
</p>
<p>
The word "verifiable" in the terms [=verifiable credential=] and
[=verifiable presentation=] refers to the characteristic of a [=credential=]
or [=presentation=] as being able to be [=verified=] by a [=verifier=],
as defined in this document. Verifiability of a credential does not imply
the truth of [=claims=] encoded therein. Instead, upon establishing the
authenticity and currency of a [=verifiable credential=] or
[=verifiable presentation=], a [=verifier=] validates the included [=claims=] using
their own business rules before relying on them. Such reliance only occurs after
evaluating the issuer, the proof, the subject, and the claims against one or
more verifier policies.
</p>
</section>
<section class="informative">
<h3>Ecosystem Overview</h3>
<p>
This section describes the roles of the core actors and the relationships
between them in an ecosystem where one expects [=verifiable credentials=]
to be useful. A role is an abstraction that might be implemented in many
different ways. The separation of roles suggests likely interfaces and
protocols for standardization. This specification introduces the following
roles:
</p>
<dl>
<dt>[=holder=]</dt>
<dd>
A role an [=entity=] might perform by possessing one or more [=verifiable
credentials=] and generating [=verifiable presentations=] from them. A holder is
often, but not always, a [=subject=] of the [=verifiable credentials=] they are
holding. Holders store their [=credentials=] in [=credential repositories=].
Example holders include students, employees, and customers.
</dd>
<dt>[=issuer=]</dt>
<dd>
A role an [=entity=] can perform by asserting [=claims=] about one or more
[=subjects=], creating a [=verifiable credential=] from these [=claims=], and
transmitting the [=verifiable credential=] to a [=holder=]. For example, issuers
include corporations, non-profit organizations, trade associations, governments,
and individuals.
</dd>
<dt>[=subject=]</dt>
<dd>
A thing about which [=claims=] are made. Example subjects include human beings,
animals, and things.
</dd>
<dt>[=verifier=]</dt>
<dd>
A role an [=entity=] performs by receiving one or more [=verifiable
credentials=], optionally inside a [=verifiable presentation=] for processing.
Example verifiers include employers, security personnel, and websites.
</dd>
<dt>[=verifiable data registry=]</dt>
<dd>
A role a system might perform by mediating the creation and [=verification=] of
identifiers, [=verification material=], and other relevant data, such as
[=verifiable credential=] schemas, revocation registries, and so on, which might
require using [=verifiable credentials=]. Some configurations might require
correlatable identifiers for [=subjects=]. Some registries, such as ones for
UUIDs and [=verification material=], might just act as namespaces for
identifiers. Examples of verifiable data registries include trusted databases,
decentralized databases, government ID databases, and distributed ledgers. Often,
more than one type of verifiable data registry used in an ecosystem.
</dd>
</dl>
<figure id="roles">
<img style="margin: auto; display: block; width: 100%;"
src="diagrams/ecosystem.svg" alt="diagram showing how
credentials flow from issuer to holder and
presentations flow from holder to verifier where all
three parties can use information from a logical
verifiable data registry">
<figcaption style="text-align: center;">
The roles and information flows forming the basis for this
specification.
</figcaption>
</figure>
<p class="note" title="Other types of ecosystems exist">
[[[#roles]]] above provides an example ecosystem to ground the
rest of the concepts in this specification. Other ecosystems exist, such as
protected environments or proprietary systems, where
[=verifiable credentials=] also provide benefits.
</p>
<p>
This ecosystem contrasts with the typical two-party or federated identity
provider models. An identity provider, sometimes abbreviated as <em>IdP</em>,
is a system for creating, maintaining, and managing identity information for
[=holders=] while providing authentication services to [=relying party=]
applications within a federation or distributed network. In a federated
identity model, the [=holder=] is tightly bound to the identity provider.
This specification avoids using "identity provider," "federated identity," or
"relying party" terminology, except when comparing or mapping these concepts
to other specifications. This specification decouples the identity provider
concept into two distinct concepts: the [=issuer=] and the [=holder=].
</p>
<p class="note" title="Subjects are not always Holders">
In many cases, the [=holder=] of a [=verifiable credential=] is the subject, but
in some instances it is not. For example, a parent (the [=holder=]) might hold
the [=verifiable credentials=] of a child (the [=subject=]), or a pet owner (the
[=holder=]) might hold the [=verifiable credentials=] of their pet (the
[=subject=]). For more information about these exceptional cases, see the
<a href="https://w3c.github.io/vc-imp-guide/#subject-holder-relationships">
Subject-Holder Relationships</a> section in the [[[VC-IMP-GUIDE]]].
</p>
<p>
For a deeper exploration of the [=verifiable credentials=] ecosystem and
a concrete lifecycle example, please refer to [[[VC-OVERVIEW]]] [[?VC-OVERVIEW]].
</p>
</section>
<section id="conformance" class="normative">
<p>
A <dfn>conforming document</dfn> is a
<a data-cite="JSON-LD11-API#compaction-algorithms">compacted</a> JSON-LD
document that complies with all of the relevant "MUST" statements in this
specification. Specifically, the relevant normative "MUST" statements in
Sections [[[#basic-concepts]]], [[[#advanced-concepts]]], and
[[[#syntaxes]]] of this document MUST be enforced.
A conforming document MUST be either a [=verifiable credential=]
with a media type of `application/vc` or a [=verifiable presentation=]
with a media type of `application/vp`. A conforming document MUST be
secured by at least one securing mechanism as described in Section
[[[#securing-mechanisms]]].
</p>
<p>
A <dfn class="lint-ignore">conforming issuer implementation</dfn> produces
[=conforming documents=], MUST include all required properties in the
[=conforming documents=] it produces, and MUST secure the [=conforming
documents=] it produces using a securing mechanism described in Section
[[[#securing-mechanisms]]].
</p>
<p>
A <dfn class="lint-ignore">conforming verifier implementation</dfn>
consumes [=conforming documents=], MUST perform [=verification=] on a
[=conforming document=] as described in Section
[[[#securing-mechanisms]]], MUST check that each
required property satisfies the normative requirements for that property, and
MUST produce errors when non-[=conforming documents=] are detected.
</p>
<p>
This specification includes both required and optional properties. Optional
properties MAY be ignored by [=conforming issuer implementations=] and
[=conforming verifier implementations=].
</p>
<p>
This document also contains examples that contain characters that are invalid
JSON, such as inline comments (`//`) and the use of ellipsis
(`...`) to denote information that adds little value to the example.
Implementers are cautioned to remove this content if they desire to use the
information as a valid document.
</p>
<p class="note" title="Human-readable texts in English are illustrative">
Examples provided throughout this document include descriptive properties, such as
`name` and `description`, with values in English to simplify the concepts in each
example of the specification. These examples do not necessarily reflect the data
structures needed for international use, described in more detail in
Section [[[#internationalization-considerations]]].
</p>
</section>
</section>
<section class="normative">
<h2>Terminology</h2>
<p>
The following terms are used to describe concepts in this specification.
</p>
<dl class="termlist definitions">
<dt><dfn class="export" data-lt="claims">claim</dfn></dt>
<dd>
An assertion made about a [=subject=].
</dd>
<dt><dfn class="export" data-lt="credential|credentials">credential</dfn></dt>
<dd>
A set of one or more [=claims=] made by an [=issuer=]. The [=claims=]
in a credential can be about different [=subjects=]. The definition of
credential used in this specification differs from,
<a href="https://csrc.nist.gov/glossary/term/credential">NIST's definitions of
credential</a>.
</dd>
<dt><dfn data-lt="decentralized identifiers|DID|DIDs">decentralized identifier</dfn></dt>
<dd>
A portable URL-based identifier, also known as a <strong><em>DID</em></strong>,
is associated with an [=entity=]. These identifiers are most often used in a
[=verifiable credential=] and are associated with [=subjects=] such that a
[=verifiable credential=] can be easily ported from one
[=credential repository=] to another without reissuing the [=credential=].
An example of a DID is `did:example:123456abcdef`. See the
[[[?DID-CORE]]] specification for further details.
</dd>
<dt><dfn class="lint-ignore" data-lt="decentralized identifier documents|DID document|DID documents">decentralized identifier document</dfn></dt>
<dd>
Also referred to as a <strong><em>DID document</em></strong>, this is a document
that is accessible using a [=verifiable data registry=] and contains
information related to a specific [=decentralized identifier=], such as the
associated [=credential repository=] and [=verification material=]. See the
[[[?DID-CORE]]] specification for further details.
</dd>
<dt><dfn data-lt="default graph">default graph</dfn></dt>
<dd>
The [=graph=] containing all [=claims=] that are not explicitly part of
a [=named graph=].
</dd>
<dt><dfn class="lint-ignore">digital signature</dfn></dt>
<dd>
A mathematical scheme for demonstrating the authenticity of a digital message.
</dd>
<dt><dfn data-lt="entities|entity's">entity</dfn></dt>
<dd>
Anything that can be referenced in statements as an abstract or concrete noun.
Entities include but are not limited to people, organizations, physical things,
documents, abstract concepts, fictional characters, and arbitrary text. Any
entity might perform roles in the ecosystem, if it can do so. Note
that some entities fundamentally cannot take actions, for example, the string "abc"
cannot issue credentials.
</dd>
<dt><dfn data-lt="graphs">graph</dfn></dt>
<dd>
A set of claims, forming a network of information composed of [=subjects=]
and their relationship to other [=subjects=] or data. Each [=claim=] is
part of a graph; either explicit in the case of [=named graphs=], or
implicit for the [=default graph=].
</dd>
<dt><dfn class="export" data-lt="holders|holder's|holders'">holder</dfn></dt>
<dd>
A role an [=entity=] might perform by possessing one or more
[=verifiable credentials=] and generating [=verifiable presentations=]
from them. A holder is often, but not always, a [=subject=] of the
[=verifiable credentials=] they are holding. Holders store their
[=credentials=] in [=credential repositories=].
</dd>
<dt><dfn class="export" data-lt="issuers|issuer's">issuer</dfn></dt>
<dd>
A role an [=entity=] can perform by asserting [=claims=] about one or
more [=subjects=], creating a [=verifiable credential=] from these
[=claims=], and transmitting the [=verifiable credential=] to a
[=holder=].
</dd>
<dt><dfn data-lt="named graphs">named graph</dfn></dt>
<dd>
A [=graph=] associated with specific properties, such as
`verifiableCredential`. These properties
result in separate [=graphs=] that contain all [=claims=] defined in the
corresponding JSON objects.
</dd>
<dt><dfn class="export" data-lt="presentation|presentations">presentation</dfn></dt>
<dd>
Data derived from one or more [=verifiable credentials=] issued by one or
more [=issuers=] that is shared with a specific [=verifier=].
</dd>
<dt><dfn class="export" data-lt="credential repositories">credential repository</dfn></dt>
<dd>
Software, such as a file system, storage vault, or personal [=verifiable
credential=] wallet, that stores and protects access to [=holders'=]
[=verifiable credentials=].
</dd>
<dt><dfn class="export">selective disclosure</dfn></dt>
<dd>
The ability of a [=holder=] to make fine-grained decisions about what
information to share.
</dd>
<dt><dfn class="export">unlinkable disclosure</dfn></dt>
<dd>
A type of [=selective disclosure=] where [=presentations=] cannot be correlated
between [=verifiers=].
</dd>
<dt><dfn class="export" data-lt="subjects|subject's">subject</dfn></dt>
<dd>
A thing about which [=claims=] are made.
</dd>
<dt><dfn class="lint-ignore">user agent</dfn></dt>
<dd>
A program, such as a browser or other Web client, that mediates the
communication between [=holders=], [=issuers=], and [=verifiers=].
</dd>
<dt><dfn class="export" data-lt="claim validation|validate">validation</dfn></dt>
<dd>
The assurance that a [=claim=] from a specific [=issuer=] satisfies the business
requirements of a [=verifier=] for a particular use. This specification defines
how verifiers verify [=verifiable credentials=] and [=verifiable
presentations=]. It also specifies that [=verifiers=] validate claims in
[=verifiable credentials=] before relying on them. However, the means for such
validation vary widely and are outside the scope of this specification.
[=Verifiers=] trust certain [=issuers=] for certain claims and apply their own
rules to determine which claims in which [=credentials=] are suitable for use by
their systems.
</dd>
<dt><dfn class="export">verifiable credential</dfn></dt>
<dd>
A tamper-evident [=credential=] whose authorship can be cryptographically
verified. Verifiable credentials can be used to build
[=verifiable presentations=], which can also be cryptographically verifiable.
</dd>
<dt><dfn class="export" data-lt="verifiable data registries">verifiable data registry</dfn></dt>
<dd>
A role a system might perform by mediating the creation and [=verification=]
of identifiers, [=verification material=], and other relevant data, such as
[=verifiable credential=] schemas, revocation registries,
and so on, which might require using [=verifiable credentials=]. Some
configurations might require correlatable identifiers for [=subjects=]. Some
registries, such as ones for UUIDs and [=verification material=], might act
as namespaces for identifiers.
</dd>
<dt><dfn class="export">verifiable presentation</dfn></dt>
<dd>
A tamper-evident presentation of information encoded in such a way that
authorship of the data can be trusted after a process of cryptographic
verification. Certain types of verifiable presentations might contain data that
is synthesized from, but does not contain, the original [=verifiable credentials=]
(for example, zero-knowledge proofs).
</dd>
<dt><dfn class="export" data-lt="verify|verified|verifying|verifiable|verifiability">verification</dfn></dt>
<dd>
The evaluation of whether a [=verifiable credential=] or [=verifiable
presentation=] is an authentic and current statement of the issuer or presenter,
respectively. This includes checking that the credential or presentation
conforms to the specification, the securing mechanism is satisfied, and, if
present, the status check succeeds. Verification of a credential does not imply
evaluation of the truth of [=claims=] encoded in the credential.
</dd>
<dt><dfn class="export" data-lt="verifier|verifiers|verifier's|credential verifiers|credential verifier's">verifier</dfn></dt>
<dd>
A role an [=entity=] performs by receiving one or more
[=verifiable credentials=], optionally inside a
[=verifiable presentation=] for processing. Other specifications might refer
to this concept as a <dfn data-lt="relying parties">relying party</dfn>.
</dd>
<dt><dfn data-lt="verification material">verification material</dfn></dt>
<dd>
Information that is used to verify the security of cryptographically
protected information. For example, a cryptographic public key is used to verify
a digital signature associated with a [=verifiable credential=].
</dd>
<dt><dfn data-lt="URL|URLs">URL</dfn></dt>
<dd>
A Uniform Resource Locator, as defined by the [[[URL]]]. URLs can be
dereferenced to result in a resource, such as a document. The rules
for dereferencing, or fetching, a URL are defined by the URL [=url/scheme=].
This specification does not use the term URI or IRI because those terms have
been deemed to be confusing to Web developers.
</dd>
</dl>
</section>
<section class="informative">
<h2>Core Data Model</h2>
<p>
The following sections outline core data model concepts, such as [=claims=],
[=credentials=], [=presentations=], [=verifiable credentials=], and
[=verifiable presentations=], which form the foundation of this
specification.
</p>
<p class="note"
title="The difference between a credential and a verifiable credential">
Readers might note that some concepts described in this section, such as
[=credentials=] and [=presentations=], do not have media types defined by
this specification. However, the concepts of a [=verifiable credential=] or a
[=verifiable presentation=] are defined as [=conforming documents=] and
have associated media types. The concrete difference between these concepts
— between [=credential=] and [=presentation=] vs. [=verifiable
credential=] and [=verifiable presentation=] — is simply the fact
that the "verifiable" objects are secured in a cryptographic
way, and the others are not. For more details, see Section
[[[#securing-mechanisms]]].
</p>
<section class="informative">
<h3>Claims</h3>
<p>
A [=claim=] is a statement about a [=subject=]. A [=subject=] is a
thing about which [=claims=] can be made. [=Claims=] are expressed using
<strong><em>subject</em></strong>-<dfn data-lt="property|properties">
property</dfn>-<dfn class="lint-ignore">value</dfn> relationships.
</p>
<figure id="basic-structure">
<img style="margin: auto; display: block; width: 80%;"
src="diagrams/claim.svg" alt="subject has a property which
has a value">
<figcaption style="text-align: center;">
The basic structure of a claim.
</figcaption>
</figure>
<p>
The data model for [=claims=], illustrated in [[[#basic-structure]]]
above, is powerful and can be used to express a large variety of statements. For
example, whether someone graduated from a particular university can be expressed
as shown in [[[#basic-example]]] below.
</p>
<figure id="basic-example">
<img style="margin: auto; display: block; width: 80%;"
src="diagrams/claim-example.svg" alt="Pat has an alumniOf
property whose value is Example University">
<figcaption style="text-align: center;">
A basic claim expressing that Pat is an alum of "Example University".
</figcaption>
</figure>
<p>
Individual [=claims=] can be merged together to express a [=graph=] of
information about a [=subject=]. The example shown in
[[[#multiple-claims]]] below extends the previous [=claim=] by
adding the [=claims=] that Pat knows Sam and that Sam is employed as a
professor.
</p>
<figure id="multiple-claims">
<img style="margin: auto; display: block; width: 90%;"
src="diagrams/claim-extended.svg" alt="extends previous
diagram with another property called knows whose value is
Sam, and Sam has a property jobTitle whose value is Professor">
<figcaption style="text-align: center;">
Multiple claims can be combined to express a graph of information.
</figcaption>
</figure>
<p>
To this point, the concepts of a [=claim=] and a [=graph=] of information
are introduced. More information is expected to be added to the graph in order
to be able to trust [=claims=], more information is
expected to be added to the graph.
</p>
</section>
<section class="informative">
<h3>Credentials</h3>
<p>
A [=credential=] is a set of one or more [=claims=] made by the same [=entity=].
[=Credentials=] might also include an identifier and metadata to describe
properties of the [=credential=], such as the [=issuer=], the validity date and
time period, a representative image, [=verification material=], status
information, and so on. A
[=verifiable credential=] is a set of tamper-evident [=claims=] and metadata
that cryptographically prove who issued it. Examples of [=verifiable
credentials=] include, but are not limited to, digital employee identification
cards, digital driver's licenses, and digital educational certificates.
</p>
<figure id="basic-vc">
<img style="margin: auto; display: block; width: 50%;"
src="diagrams/vc.svg" alt="a Verifiable
Credential contains Credential Metadata, Claim(s), and
Proof(s)">
<figcaption style="text-align: center;">
Basic components of a verifiable credential.
</figcaption>
</figure>
<p>
[[[#basic-vc]]] above shows the basic components of a
[=verifiable credential=], but abstracts the details about how [=claims=]
are organized into information [=graphs=], which are then organized into
[=verifiable credentials=].
</p>
<p>
[[[#info-graph-vc]]] below shows a more complete depiction of a
[=verifiable credential=] using an [=embedded proof=] based on
[[[?VC-DATA-INTEGRITY]]]. It is composed of at least two information [=graphs=].
The first of these information [=graphs=], the [=verifiable credential graph=]
(the [=default graph=]), expresses the [=verifiable credential=]
itself through [=credential=] metadata and other [=claims=]. The second
information [=graph=], referred to by the `proof` property, is the
<dfn>proof graph</dfn> of the [=verifiable credential=] and is a separate
[=named graph=]. The [=proof graph=] expresses the digital proof, which, in this
case, is a digital signature. Readers who are interested in the need for
multiple information graphs can refer to Section
[[[#verifiable-credential-graphs]]].
</p>
<figure id="info-graph-vc">
<img style="margin: auto; display: block; width: 100%;"
src="diagrams/vc-graph.svg" alt="Diagram with a collections of
claims for a 'verifiable credential graph' on top
connected via a proof property (or predicate) to a 'verifiable credential proof
graph' on the bottom. The claims for a verifiable credential include 'Credential
123' as a subject with 4 properties: 'type' of value ExampleAlumniCredential,
'issuer' of Example University, 'validFrom' of 2010-01-01T19:23:24Z, and
credentialSubject of Pat, who also has an alumniOf property with value of
Example University. The verifiable credential proof graph has an object
'Signature 456' subject with 5 properties: 'type' of DataIntegrityProof,
'verificationMethod' of Example University Public Key 7, 'created' of
2017-06-18T21:19:10Z, a 'nonce' of 34dj239dsj328, and 'proofValue' of
'zBavE110…3JT2pq'. The verifiable credential graph is also annotated with the
parenthetical remark '(the default graph)', the verifiable credential proof
graph is annotated with the parenthetical remark '(a named graph)'.">
<figcaption style="text-align: center;">
Information graphs associated with a basic verifiable credential, using an [=embedded proof=]
based on [[[VC-DATA-INTEGRITY]]] [[?VC-DATA-INTEGRITY]].
</figcaption>
</figure>
<p>
[[[#info-graph-vc-jwt]]] below shows the same [=verifiable credential=]
as [[[#info-graph-vc]]], but secured using JOSE [[?VC-JOSE-COSE]]. The
payload contains a single information graph, which is the [=verifiable
credential graph=] containing [=credential=] metadata and other [=claims=].
</p>
<figure id="info-graph-vc-jwt">
<img style="margin: auto; display: block; width: 100%;"
src="diagrams/vc-jwt.svg"
alt="Diagram with, on the left, a box, labeled as
'SD-JWT (Decoded)', and with three textual labels stacked vertically,
namely 'Header', 'Payload', and 'Signature'. The 'Header' label is
connected, with an arrow, to a separate rectangle on the right hand
side containing six text fields: 'kid: aB8J-_Z', 'alg: ES384', and
'cty: vc', 'iss: https://example.com', 'iat: 1704690029', and 'typ:
vc+sd-jwt'. The 'Payload' label on the left side is connected,
with an arrow, to a separate rectangle, containing a single graph. The
rectangle has a label: 'verifiable credential graph (serialized in
JSON)' The claims in the graph include 'Credential 123' as a subject
with 4 properties: 'type' with value 'ExampleAlumniCredential',
'issuer' with value 'Example University', 'validFrom' with value
'2010-01-01T19:23:24Z', and 'credentialSubject' with value 'Pat', who
also has an 'alumniOf' property with value 'Example University'.
Finally, the 'Signature' label on the left side is connected, with an
arrow, to a separate rectangle, containing a single text field:
'DtEhU3ljbEg8L38VWAfUA...'.
">
<figcaption style="text-align: center;">
Information graphs associated with a basic verifiable credential,
using an [=enveloping proof=] based on [[[VC-JOSE-COSE]]]
[[?VC-JOSE-COSE]].
</figcaption>
</figure>
</section>
<section class="informative">
<h3>Presentations</h3>
<p>
Enhancing privacy is a key design feature of this specification. Therefore, it
is crucial for [=entities=] using this technology to express only
the portions of their personas that are appropriate for given situations. The
expression of a subset of one's persona is called a [=verifiable presentation=].
Examples of different personas include a person's professional persona,
online gaming persona, family persona, or incognito persona.
</p>
<p>
A [=verifiable presentation=] is <dfn class="lint-ignore">created</dfn> by a
[=holder=], can express data from multiple [=verifiable credentials=], and can
contain arbitrary additional data. They are used to present [=claims=] to a
[=verifier=]. It is also possible to present [=verifiable credentials=]
directly.
</p>
<p>
The data in a [=presentation=] is often about the same [=subject=] but might
have been issued by multiple [=issuers=]. The aggregation of this information
expresses an aspect of a person, organization, or [=entity=].
</p>
<figure id="basic-vp">