Understanding Digital Identity Credentials

What Is a Digital Identity Credential?: A digital identity credential is a digital representation of identity or attributes. Mobile Driver's Licenses, EUDI Wallet attestations, signed national digital IDs, and ePassports use different formats and assurance models. Supported formats can provide cryptographic authenticity, and some presentation flows can operate offline.

These credential types do not all use the same format or assurance model. Cryptographic authenticity is common to mdoc, signed QR, and ePassport credentials, while selective disclosure applies only to compatible credential and presentation formats. Offline operation also depends on the document, protocol, and deployment. The sections below explain those differences.

Mobile Driver's Licenses (mDL)

mDL Overview: A mobile driving licence is a digital credential implemented using standards such as ISO/IEC 18013-5. It supports cryptographic authenticity checks and data-minimized presentation with compatible wallets and verifiers.

What is a Mobile Driving License (mDL)?

A Mobile Driving License (mDL) is a digital driving credential held in a compatible wallet. International standards provide a common technical basis for presentation and verification across participating ecosystems.

Unlike a photo of a licence, an mDL can provide cryptographic authenticity and data-integrity checks. Compatible wallets can show requested data and ask the holder to approve presentation.

Key Benefits of mDL

Key benefits of the mDL:

• Convenience: Carry your driving license securely on your mobile device, making it readily accessible whenever you need it

• Holder Interaction: Compatible wallets can show requested information and ask the holder to approve presentation

• Cryptographic Security: Advanced cryptographic mechanisms protect against forgery, cloning, and eavesdropping, ensuring the integrity and authenticity of your data

• Privacy-Aware Design: Supports data minimization and transaction-specific disclosure when implemented by compatible wallets and verifiers

• Interoperability: International standards provide a common basis for compatible wallets and verification systems

The mDL Ecosystem: Key Players

Several essential entities work together to ensure your mDL operates securely and effectively:

mDL Holder (You)

• Compatible wallets display the requested data before presentation

• The holder can approve or decline supported presentation requests

Issuing Authority (IA)

• Official organizations like Department of Motor Vehicles that issue your driving license

• Responsible for digitally signing your mDL data and ensuring secure provisioning

• Maintains the infrastructure for the most current version of your credentials

mDL Verifiers and Readers

• Law enforcement officers, retail clerks, airline agents, and other authorized personnel

• Use specialized devices or services to retrieve and verify your mDL data

• Encouraged to request only the minimum necessary data for their specific use case

VICAL Providers

• Organizations that compile and distribute lists of trusted Issuing Authority certificates

• Provide issuer certificate information used by mDL readers to authenticate data origin and integrity

Your mDL Data Elements

Your mDL contains carefully organized information designed for flexible, privacy-respecting sharing:

Mandatory Information

• Core identification details: name, birth date, photo

• License information: issue/expiry dates, document number, issuing authority

• Driving privileges: vehicle categories, restrictions, conditions

Optional Information

• Physical characteristics: height, weight, eye/hair color

• Location data: place of birth, resident address

• Biometric templates for enhanced security

Privacy-Enhanced Features

• Age Attestations: Verify "age over 21" without revealing exact birth date

• Selective Disclosure: Compatible presentations can limit the information shared

• Domestic Customization: Country-specific data elements when needed

Enhanced Capabilities: Online Interactions (ISO/IEC TS 18013-7)

Building on the ISO/IEC 18013-5 foundation, this companion standard introduces expanded functionality:

• Online Presentation: Present your mDL to verifiers over the internet

• OpenID Integration: Direct presentation to online verifiers using standardized protocols

• API Integration: Integrates into broader digital credential ecosystems

Real-World Applications

Your mDL serves you in numerous scenarios:

• Traffic Stops: Secure, contactless presentation to law enforcement

• Age Verification: Privacy-preserving age confirmation for purchases

• Airport Security: Faster identity verification for travel

• Online Services: Remote identity verification for digital services

• Vehicle Rentals: Quick, secure credential verification

Photo ID (ISO/IEC 23220 series)

The ISO/IEC 23220 series generalizes the mdoc model beyond driver's licenses to any photo identity credential. Where ISO/IEC 18013-5 defines the mobile driver's license, the 23220 series defines the building blocks for identity management via mobile devices: ISO/IEC 23220-2 specifies the data objects and namespace for a generic photo ID, and ISO/IEC TS 23220-4 specifies the operational-phase protocols, including the Photo ID profile with document type org.iso.23220.photoid.1.

Compatible Photo ID mdocs can reuse mdoc presentation and verification building blocks while retaining their own data profile. Apple's Digital ID is a production example: Apple documents it as a mobile document created from a valid U.S. passport on compatible devices running iOS 26.1 or later, with responses validated using ISO/IEC 23220-2 and functionality inherited from ISO/IEC 18013-5. ONEPROOF SDKs verify compatible Photo ID mdoc credentials alongside mDLs through the same product integration.

Why a second standard matters to verifiers

• Broader credential coverage: Photo ID mdocs can represent passports and national IDs, not just driving privileges

• Same verification flow: a reader that performs ISO mdoc verification can support both document types through one pipeline

• Growing wallet support: major wallets now hold credentials of both types, so verifiers should expect either at presentment

EUDI: the European Digital Identity Wallet

The European Digital Identity (EUDI) Wallet is the credential framework created under the EU's eIDAS 2.0 regulation. It gives every EU member state a standardized way to issue digital identity and attribute credentials, such as national ID, driving credentials, and other attestations, into a wallet that citizens control on their own device.

Like an mDL, an EUDI Wallet credential is digitally signed by its issuing member state and presented to relying parties using standards-based protocols, so verification does not depend on any single central system. A verifier requesting a credential only receives the specific attributes a transaction requires, following the same data minimization principle used across digital identity standards.

What verifiers need to accept EUDI Wallet credentials:

• Support for the presentation protocols used by EUDI Wallets, so credentials can be requested and received in a standardized format

• The ability to validate the issuing member state's cryptographic signature and trust chain

• A device-local verification path that does not require routing citizen data through a third party

National Digital IDs

Beyond driver's licenses, many countries issue national digital identity credentials using country-specific formats. MiDNI, Spain's national digital identity, is a production example: it is accepted at 300+ locations across Spain and presented as a signed QR credential.

MiDNI is not an mdoc and should not be treated as one. Its signed, self-contained QR presentation has its own certificate and verification semantics. Other national ID programs may use different credential formats and presentation protocols.

ePassports

An ePassport is a physical passport with an embedded chip, standardized under ICAO 9303. The chip stores the holder's identity data along with a digital signature from the issuing government, which allows the passport's authenticity to be verified cryptographically rather than relying on visual inspection of the physical document alone.

Because the signature and data live on the chip itself, ePassport checks can be completed offline. ONEPROOF EDGE hardware (Patent Pending) connects the document to customer-controlled host software without requiring a cloud service. ePassport support is available through our early access program.

How Verification Works

Verification is format specific. Compatible mdoc credentials, signed QR credentials, and ePassports can all support cryptographic authenticity checks, but their transports, signatures, trust inputs, disclosure behavior, and result semantics differ.

1. Device Engagement

• Proximity Methods: Tap a device to an NFC reader, scan a QR code, or read an ePassport chip directly

• Device Retrieval: Compatible mdoc flows can exchange data using Bluetooth Low Energy or NFC without an internet connection

• Format-Specific Transport: Session encryption and transport protections depend on the credential and presentation protocol

2. Cryptographic Signature Verification

• The verifier applies the signature and trust checks defined for the credential format

• Any tampering with the underlying data invalidates the signature, so forged or altered credentials are rejected

• Supported offline flows can complete without a live call to ONEPROOF or the issuer

3. Selective Disclosure

• Compatible wallets can show the requested data and ask the holder to approve presentation

• Compatible formats can disclose specific attributes, such as an age threshold rather than a full birth date

• Privacy properties depend on the credential format, wallet, verifier request, and implementation

Advanced Security Features

Digital identity credentials incorporate multiple layers of security protection:

Cryptographic Protection

• Session Protection: Compatible presentation protocols use their defined channel and session protections

• Digital Signatures: Applicable credential data is checked against the signer and trust model defined for its format

• Device Binding: Compatible credentials can use holder-controlled key material to add device-binding checks

Privacy Protection

• Holder Interaction: Compatible wallets can provide just-in-time information about presentation requests

• Data Minimization: Compatible formats can limit presentation to the information needed for a transaction

• Transaction Separation: Compatible protocols can use session-specific cryptographic material to help isolate exchanges

• Request Design: Well-designed verifier requests reduce the personal data shared for a transaction

Getting Started with Digital Identity Credentials

Here's what you need to know to get started:

• Check Availability: Verify if your state or country offers mDL, EUDI Wallet, or national digital ID services

• Download the App: Install your jurisdiction's official wallet application

• Secure Setup: Follow the secure enrollment process with identity verification

• Learn the Features: Familiarize yourself with privacy controls and sharing options

Frequently Asked Questions

What is a digital identity credential?

A digital identity credential is a digital representation of identity or attributes. Mobile Driver's Licenses, EUDI Wallet attestations, signed national digital IDs, and ePassports use different formats and assurance models. Supported formats can provide cryptographic authenticity, and some presentation flows can operate offline.

What is the EUDI Wallet?

The European Digital Identity (EUDI) Wallet is a credential framework defined under the EU's eIDAS 2.0 regulation. It lets EU member states issue digital identity and attribute credentials that can be verified cryptographically across borders and industries, using standards-based presentation protocols.

Is an ePassport the same as a physical passport?

An ePassport is a physical passport with an embedded chip, standardized under ICAO 9303. The chip stores your identity data and a digital signature from the issuing government, which lets a verifier check the passport's authenticity cryptographically, offline, without needing a live connection to the issuing country.

What standard does Apple's Digital ID use?

Apple's Digital ID can be created from a valid U.S. passport on compatible devices running iOS 26.1 or later. Apple documents it as a mobile document whose response can be validated using ISO/IEC 23220-2 and that inherits functionality from ISO/IEC 18013-5.

Is mDL accepted everywhere?

mDL acceptance is growing rapidly. While not yet universal, many states, law enforcement agencies, and businesses are implementing mDL verification capabilities. Always carry your physical license as backup until full adoption is achieved.

What if my phone battery dies?

If the phone or wallet cannot operate, the holder may be unable to present the mDL. Carrying the physical license as backup remains advisable where required or accepted.

Can my digital identity data be tracked?

Digital identity systems can support data minimization and transaction-specific sessions. Actual privacy properties depend on the credential format, wallet, verifier, deployment, and requested data.

Contact Information

Questions about digital identity credentials, implementation, or privacy? Contact us:

• General Inquiries: info@oneproof.com

• Technical Support: support@oneproof.com

• Privacy Questions: privacy@oneproof.com

• Partnership Opportunities: partnerships@oneproof.com

Stay Updated

The digital identity landscape continues to evolve with new credential types, expanded acceptance, and enhanced security measures. Visit our Understanding Digital Identity Credentials page regularly for the latest information about mDL, EUDI, national digital IDs, ePassports, and how they are verified.

Digital identity credentials replace physical documents with cryptographically verifiable, privacy-preserving equivalents.