The official SAP integration module is provided by pernexas, and is called connexas. There is no SAP integration out-of-the-box and without an integration module such as this (or from a different vendor) you will not have any luck.
Thank you so much for your answer. But actually I couldn't find any installation or integration document/website about this issue. So I don't know what can I need to do in SAP side and Alfresco side. Is there any documentation about Alfresco-SAP installation and integration steps?