Prior to version 1.3.6 the PI-SDK the default implicit connection behavior is as described under the “Trust Connections” section above. The connecting user and his machine are received and validated by the server then the trust table is consulted to determine if any trusts are available. If no suitable trusts are found, the server tells the PI-SDK and it then tries a connection using the configured default user and a blank password.
With PI-SDK version 1.3.6, the setup program establishes the initial default implicit connection options to be tried in order as:
These options can be removed, reordered or added to as deemed appropriate. Not all servers will support all authentication options. An option that is not supported is simply skipped by the server when it is authenticating.
On a PI 3.4.380 and later server, until PI Identities are created and mappings to Windows principals established, SSPI is not in effect. This means that without specific action, upgrading the server and the PI-SDK results in effective default implicit authentication of Trust followed by Default User, essentially the same as in earlier servers and PI-SDK versions.