When making calls to instances of Microsoft Dynamics 365, you may notice that some calls are very slow, often taking several seconds to complete. This scenario is usually a side effect of using basic (username/password) authentication to create your Dynamics instance. Basic authentication connections require the handshake process to occur more frequently, particularly when the same user name and password are used to log in elsewhere. This handshake process can add several seconds to API calls.
To fix this issue, we encourage users to use OAuth 2.0 to authenticate connector instances. This prevents the issue of credentials being used elsewhere and thus requiring the handshake process to take place. For more information on how to create instances of Dynamics via OAuth 2.0, see our documentation.