EMA C++ RDM Usage Guide : 3 Login Domain : 3.7 Specific Usage: Login Credentials Update Feature
 
3.7 Specific Usage: Login Credentials Update Feature
Internally Enterprise Message API stores all login credentials (e.g., user name, name type, login attributes), so it can use them later during connection recovery phase. These credentials can be changed by the application at any point in time after a connection and login is established. To change login credentials, an application needs to reissue a login request message with the new credentials. This new request message must meet the following criteria:
A new user name parameter, different from the one specified on a prior request or reissue, must be specified.
The NameType parameter must be specified as USER_TOKEN on all, the initial request and all subsequent reissues.
The Interactions set in the reissue must match the original InteractionType.
If all of the above conditions/criteria are met, Enterprise Message API will send the reissue with the new login credentials to the server and will internally store the new/updated login credentials to be used later during connection recovery. If all of the above conditions/criteria are not met, Enterprise Message API will apply the standard login reissue processing. If no new/updated login credentials are specified by application, during the connection recovery phase Enterprise Message API will use the previously used ones.