Create a multiplayer session. Fails if the session already exists.
UpdateOrCreateNew
Either update or create a session. Doesn’t care whether the session exists.
UpdateExisting
Updates an existing multiplayer session. Fails if the session doesn’t exist.
SynchronizedUpdate
Updates an existing multiplayer session. Fails with HTTP_E_STATUS_PRECOND_FAILED (HTTP status 412) if the ETag on the local session doesn’t match the ETag on the server. Fails if the session does not exist.