7. Non-Functional Requirements¶

Some criteria contained in this specification require network endpoints to be reachable and responsive. This includes endpoints used for resolving terms including identifiers such as the JSON-LD @context, the (identifier of an) ontology, or an URI, and also endpoints for services offered over a network such as the endpoint of an extension.

This section specifies the general non-functional requirements (NFR) under which a required endpoint is deemed to be reachable and responsive.

Compatibility area NFR-1 “Endpoint availability” extends to all endpoints referred to in a mandatory requirement with the possibility that an individual criterion for a specific endpoint may define deviating NFRs.

The verification method for every criterion in this chapter is automated: conformity can be established entirely by a conformant software agent (validator, compliance engine or test suite), based on the assessment of whether all criteria in area NFR-1 are met for all endpoints.

7.1 NFR-1 Endpoint availability¶

7.1.1 NFR-1.1 Endpoint availability scope¶

The criteria contained in compatibility area NFR-1 “Endpoint availability” shall apply to all network endpoints explicitly or implicitly referred to in this specification in the following contexts:

1. term resolves (to)
2. artifact resolved from
3. term return(s) an object
4. resolved term
5. resolvable term
6. term is resolvable
7. service (is) reachable

Here, the expressions term, artifact, and service refer to the corresponding elements in the respective criteria.

A criterion in this specification may derogate from the requirements contained in NFR-1 if and only if it explicitly includes text specifically referring to every individual criterion listed in area NFR-1 which shall not be applied for the conformity assessment.

7.1.2 NFR-1.2 Maximum time-out of a single connection attempt¶

The time-out of a single attempt to successfully complete a connection to a network endpoint shall not exceed 30 (“thirty”) seconds.

7.1.3 NFR-1.3 Maximum number of retries of connection attempts¶

The number of unsuccessful connection attempts to a single network endpoint shall not exceed 4 (four) attempts for any period of 24 (“twenty-four”) consecutive hours.

Note
This means that if a single endpoint is not reachable for 4 times 30 seconds (NFR-1.1) during a single compliance check, one has to wait for 24 hours before another compliance check is regarded successful.