# Glossary

This section provides a description of the main concepts and configuration parameters used across the Namirial Wallet APIs and services.

## General terms

- **Batch Issuance**: Allows multiple credentials to be issued within a single issuance request, supporting high-volume enterprise issuance scenarios.
- **DC API (Digital Credentials API)**: is a browser-based API that allows websites to directly interact with a Wallet installed on the user’s device to request credential issuance or presentation.
- **Key Binding**: links a credential to a Wallet-controlled cryptographic key, ensuring that the credential can only be used by its legitimate holder.
- **LoA (Level of Assurance)** : The Level of Assurance (LoA) defines the assurance level required during issuance, based on the strength of identity verification and authentication (e.g., substantial or high).
- **OID4VP** : OpenID for Verifiable Presentations (OID4VP) is the standard protocol used to request and receive Verifiable Presentations from a Wallet, enabling interoperable and secure verification flows.
- **OID4VCI**: OpenID for Verifiable Credential Issuance (OID4VCI) is the standard protocol used to issue Verifiable Credentials to a Wallet, defining secure and interoperable issuance flows.
- **PoP (Proof of Possession)**: is a cryptographic mechanism used to prove that the Wallet controls the private key associated with a credential or a presentation, preventing replay attacks.
- **Single-Use Credential**: is a credential that becomes invalid after being presented once, preventing reuse and supporting disposable attestation scenarios.
- **Verifiable Credentials** : is a digitally signed attestation issued by a trusted entity (Issuer) to a Wallet holder, containing a set of claims (attributes) about the subject. It can be securely presented to a Verifier, who can validate its authenticity and integrity by checking the cryptographic signature and related trust material.