## 4 Gaia-X
### Architecture of a Gaia-X Dataspace  
Begining Gaia-X conformant starts by entering a _Gaia-X Federation_, which is a collection of _Participants_ aiming to exchange data. Federations serve as the technical and organizational foundation for the associated databases where these exchanges occur. Each federation facilitates individual exchanges, rather than managing the entirety of its dataspaces (see Figure 3). Within this framework, so-called _Services_ act as the enablers of data exchanges, with the requesting party as the _Consumer_ and the responding party as the _Provider_. These exchanges typically involve digital data but can include physical goods or resources. Before any service is consumed, a _Contract_ must be negotiated, specifying the terms of the data exchange. This contract ensures consent is obtained beforehand. Gaia-X _Credentials_, which provide certified information about participants issued by trusted _Credential issuing entities_, help to make this consent \"informed\". The requesting party is the _Consumer_ and the responding party the _Provider_. To be precise, a service in a digital environment necessarily deals with the exchange of some kind of data, but can also include an exchange of physical goods or the provision of resources. Most of the services relevant for our use cases were completely digital however. As a core concept, before a service can be consumed, often simply meaning that the data in question can be exchanged, a _Contract_ for the consumption has to be negotiated between  
Figure 3: Diagram showing the interactions between the different entities in a Gaia-X dataspace and the resulting processes. Providers provide Services to Consumers, which they can find via a Catalog. Consumers consume the service after negotiating a contract for its usage with its Provider, which contains Credentials for relevant information. the consumer and provider. This contract represents the consent of both parties to precisely specified future data exchanges and thereby fits our requirement of obtaining consent before data exchanges take place. Consent is also implicitly respected, since data exchanges can only happen if the corresponding contracts were negotiated previously. To help the consent become informed, Gaia-X presents the concept of _Credentials_, which are information about participants given out and certified by _Credential issuing entities_, mostly institutions external to a particular contract. All parties in a contract can then request these entities to verify the information certified by them beforehand, serving as a source of truth about the issues they are negotiating, addressing the need for correctness in agreements, including informed consent. While the previous concepts are fundamental to Gaia-X, the following are less precisely specified, and were modified and adapted by us. Addressing the requirement of maintaining trust between data-exchanging parties, participants in a federation are required to obtain a particular kind of credential, certifying their identity and their participation in the federation itself. This credential can then be used in the contract and during the later service consumption. This setup enables mutual trust when combined with the corresponding real legal personal and organization identities checked during the onboarding of participants. To facilitate this, several _federation services_ are conceptualized, enabling participants to enter the federation in the first place and form contracts. Helping to find potential providers to form contracts with, participants can use one such federation service, the _Catalog_, or service registry, where providers register their services and consumers can browse them. This concept gives rise to the idea of a service ecosystem, where contracts are negotiated in an open, shared marketplace of services.