Functional Requirements

B 029	An IDS Meta Data Broker must provide capabilities to persistently store meta data conforming to the IDS Information Model. The conforming Information model has to be at least of version 3.0.0.
B 030 (B5)	The architecture of an IDS Broker may be based on the general Connector architecture. Therefore, an IDS Broker is a specialized IDS Connector, which might not implement some Connector specific features.
B 031	Several protocols can be implemented. The default and recommended protocol is HTTPS.
B 032 (B17)	An interaction not meant for meta-data retrieval with an IDS Meta Data Broker contains exactly one of the following functions (see also Figure 1): a) Register (a new entry) b) Update (an existing entry) c) Passivate (an existing entry) d) Activate (an existing entry) e) Remove (an existing entry)
B 033	Only the according Sovereign (defined according to IDS RAM 3.0) may register, change, or delete Connector or Resource metadata. Following restrictions apply: a) The Sovereign can authorize a third party with this task, for instance if the Sovereign it self does not operate an own IDS Connector. In this case, the requesting Connector must supply an IDS AuthorizationToken proofing his permission. b) An IDS Meta Data Broker Operator is allowed to administer the contained data. Inparticular, an IDS Meta Data Broker Operator is allowed to delete or passivate metadata if it holds trustworthy indications that for instance the respective Connector or Resource left an International Data Space or stopped responding. In any case, an IDS Meta Data Broker Operator must not manipulate metadata in anyway resulting in wrong information.
B 034 (B20)	The identifier of all IDS Resources contains a unique character sequence, which is assigned by an authorized Connector. Connectors must receive their identity key from an IDS Identity Provider. This key is based on an URI, which has to be resolvable for all IDS members (must not contain localhost or local IP addresses). This URI is called the IDS Identifier.
B 035	The IDS Identifier may be used to retrieve the linked metadata in case no Meta Data Broker is available. The URI is not used for direct addressing a Connector and therefore does not need to point to the specific Connector location.
B 036	By using authorities from the global Domain Name System (DNS), theIDS Identifier is unique between all members. The IDS recommends the usage of DNS URIs for identifiers.
B 037 (B29)	An index service must not store external RDF vocabularies, not belonging to the Information Model. See IDS-RAM 3.0 explanations for Vocabulary Hubs.
B 038 (B30)	An IDS Meta Data Broker is not responsible to validate the content of broker messages. This contains following cases a) a Connector can be reached as described by the metadata b) a Connector exposes a data endpointas published in the metadata c) a RDF vocabulary is available at the given URL
B 039 (B31)	An IDS Meta Data Broker will provide a self-information like any other Connector. In difference to other Connectors this self-information has to be supplied at a specified URL ( http(s)://<broker.authority>[:port]/<path to broker root> ) and gives additional information about the index service. This information contains additionally: a) supported (native) query languages b) supported identity providers (like Connector) c) available add-on service (like data endpoints) d) publication of local index service rules (→B18)
B 040	The attributes of B31 are specified in the IDS Information Model and have to be delivered in an RDF serialization.
B 041	An IDS Meta Data Broker uses state of the art communication encryption based on TLS. In case no TLS encryption is possible, Connectors should refuse the connection.