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Double check the proxy settings are correct.
If you are using a Java bean as your adapter, ensure you have defined the bean and set the alias configuration to use that bean instead. Also double check the class is correct and is being injected via Spring.
If a webservice is being used, ensure the web proxies are set and the URL of your webservice is listed in the Internal Exchange Info configuration under the correct service name and API spec level.
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Suggestion: Develop a set of policies to accept or deny messages based on the information that is in the exchange SAML (Subject ID, Subject Organization, Subject Role, Purpose Of Use, Home Community ID, Organization ID, Resource ID (Optional), National Provider Identifier (Optional)), and then implement a custom CONNECT policy engine adapter to enforce these policies. If a message is OK (per your policies) then you would have some assurances and feel safer about using a single username and password to communicate with your service.
How can we implement/Setup MPI?
Message Passing Interface (MPI) is not part of ConnectCONNECT. There are several Message Passing InterfaceMPI's (MPI) available like OpenMPI, MirthMatch, etc.
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