WCF或ASP.net Webservice，它使用Sap网关进行微软

I hope my question isn't too broad to answer: I am planing to create a webservice (either wcf or asp.net) to connect my Windows Desktop Software to various datasources one of them is a sap database. Is using the SAP Gateway for Microsoft the best idea for this approach? I would include the SAP Datasources in my Webservice that means my desktop application would request data and my webservice decides where it can get the data from or where to it has to save the data (mssql database, as400, sap or whatever).I hope my question isn't too broad to answer: I