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Figure 4 The sequence diagram of service negotiation in CAPTAIN
Service negotiation in CAPTAIN
Figure 4 presents a sequence message diagram that illustrates service negotiation in CAPTAIN. It includes all
negotiation elements for CAPTAIN to support the service negotiation between the P-Broker and the DASs. The result of
the negotiation is the integrated care plan that meets the needs of the end-user.
The pre-negotiation stage produces the information needed for the service negotiation stage. The DASs
publish their service descriptions to the semantic registry so that the I-Broker, then, can find their service
description during service negotiation. Then the end-user generates a request for the P- broker by choosing
and revising a care plan retrieved from the domain knowledge. Finally, the P-Broker issues the request to
the P-Broker to formulate specific queries for the DASs.
The service negotiation stage occurs between the P-Broker and the DASs. The P-Broker issues the queries,
via the I-Broker, to the DASs for the DASs’ offers. The P-Broker chooses the offers preferred by the end-
user. Then the P-Broker creates and presents the integrated care plan to the end-user.
The post-negotiation stage involves the decision-making by the end-user to accept or decline the result from
the P-Broker. The accepted integrated care plan is updated to the P-Broker’s domain knowledge and the P-
Broker will issue an acknowledgement of the end-user’s decision making to the DASs.
