Glossary
The standards of the VIN series, the API Catalogue and the interface documentation on this site use a small vocabulary consistently. Where a term below appears in a standard, it has the meaning given here unless the standard itself defines it more narrowly. The glossary is maintained by the Developer Portal of the Velocity Interoperability Network and extended as new terms are introduced by a standard or an interface.
Terms are listed alphabetically. The final column names the page of this site on which the term is principally used.
| Term | Meaning | See |
|---|---|---|
| Assertion | A signed statement issued by the Identity Service that a named person or system has been authenticated, valid for a stated period and presented by a system to a relying system. | Identity assertion |
| Assurance level | A number from 1 to 3 carried in an assertion that states how the subject was authenticated: 1 for a password alone, 2 for a password with a second factor, 3 for a hardware credential issued by a member organisation. | Identity assertion |
| Baseline | VIN-1 Interoperability Baseline: the minimum set of protocols, encodings and conduct that every connected system must support. | Standards |
| Catalogue identifier | The permanent identifier of an interface in the API Catalogue, in the series API-01, API-02 and so on. Never reused. | API Catalogue |
| Confirmed | The status of an interface that is documented in full, has been stable for three months and is issued at Version 1.0. It changes only by a new version of the standard it follows. | APIs |
| Conformance | The state of a system that implements a standard at a stated version. Conformance is declared by the member organisation and recorded, not tested, by the Developer Portal. | Conformance |
| Correction | A change to the wording of a standard that alters no requirement and does not change the version number. | Versioning |
| Declaration | The statement sent by a member organisation to the Developer Portal naming a system, the standards it implements and the version of each. | Conformance |
| Envelope | The structure defined by VIN-5 in which every message between member systems is carried: identifier, sender, recipient, sequence number, timestamp, assertion, payload type, payload and signature. | APIs |
| Incident report | A report in the VIN-3 format of an event affecting the availability, integrity, security or data quality of a connected system, submitted to a Network authority. | Incident submission |
| Interface | A defined set of operations exposed by a Network service through which member systems exchange data. Every interface follows one standard and is listed in the API Catalogue. | API Catalogue |
| Interim | The status of an interface that is available and documented but may change before it is confirmed. An Interim interface carries a version below 1.0. | APIs |
| Major revision | A new version of a standard that changes or removes a requirement, raising the first number of the version. The earlier version remains valid for twelve months. | Versioning |
| Member organisation | An organisation listed on the register of the Member Registry with the status Active and entitled to connect systems to the Network. | Registry lookup |
| Member system | A system operated by a member organisation that connects to the Network and, by declaration, conforms to VIN-1 and VIN-5 at least. | Conformance |
| Minor revision | A new version of a standard that adds to it without invalidating conforming systems, raising the second number of the version. | Versioning |
| Network authority | A department or service of the Network empowered to receive reports from, or make decisions about, member systems, such as the Status Service in respect of incidents. | — |
| Network service | A shared service of the Network, such as the Member Registry, the Identity Service or the Official Register, that exposes interfaces to member systems. | API Catalogue |
| Notice | A formal publication of the Official Register, numbered and dated, delivered to subscribing systems through the notice feed. | Notice feed |
| Operation | One named action that an interface performs on request, with a defined request and response. The operations of each interface are tabulated in its documentation. | APIs |
| Planned | The status of an interface that has been notified to the Developer Portal and assigned an identifier but is not yet available. No documentation is published for a Planned interface. | API Catalogue |
| Provider | The Network service that exposes an interface and is responsible for its operation. | API Catalogue |
| Registry record | The record of a member organisation held in the VIN-4 data model: key, organisation, kind, status, date of certification, last change and certificate reference. | Registry lookup |
| Relying system | A member system that accepts an assertion issued by the Identity Service as proof of the identity of a person or system. | Identity assertion |
| Sequence number | A number carried in every envelope, increasing by one for each message from a given sender, by which a recipient detects a missing or repeated message. | Notice feed |
| Standard | A document in the VIN series, issued at a stated version, that sets out requirements which member systems implement and to which they declare conformance. | Standards |
| Version | A number of the form major.minor identifying one issue of a standard or interface. A declaration of conformance always names a version. | Versioning |
| VIN series | The single numbered series, VIN-1 to VIN-5 at present, in which all Network standards are issued. | Standards |
| Withdrawn | The status of an interface or version that is no longer offered. A withdrawn entry remains listed with the date of its withdrawal. | APIs |
A proposal to add a term, or to correct a meaning, may be sent to contact@developer.gov.vin. Proposals that affect the wording of a standard are treated as comments on that standard and considered at its next review, as described under Versioning.