Service definitions can be created directly in the Service Definition folder or during the creation of interactions in diagrams.

During the creation of the service definition, the creation wizard presents two types of roles: "Consumer / Provider" and "Emitter / Receiver".

The "Consumer" and the "Emitter" are both initiators of the exchange.

The "Consumer / Provider" notion is used to indicate that an exchange contract exists between the consumer and the provider. When the consumer sends information requesting a particular service, a response is expected from the provider.

The "Emitter / Receiver" notion is used when the exchange occurs on the operational level to asses the possible information exchange between two nodes. With this kind of exchange, the "Emitter" sends out information to a receiver, however, a response from the receiver is not mandatory.