As John says XML-RPC actually predates SOAP. It's also simpler and thus easier to implement but SOAP has better support for handling complex types. Ultimately you have to choose the one that best meets your application requirements. I do feel strongly that HTTP is the wrong transport protocol for an RPC mechanism; BEEP is a much better choice. ... WkH p.s. RFC 3288 describes how to use SOAP over BEEP Timur Shemsedinov <Timur@niist.ntu-k To: Ward Harold/Austin/IBM@IBMUS pi.kiev.ua> cc: ietf@IETF.ORG, jstracke@centivinc.com Subject: Re[2]: Last Call: Using XML-RPC in BEEP to Proposed Standard 10/11/2002 03:38 AM Please respond to Timur Shemsedinov Ward, thanks for explanations and references. I have one more question. XMLRPC is similar to SOAP in abilities and applications, as I understand. But on my personal opinion, if to compare, XMLRPC has much more winning data representation. "Envelope" is terrible itself. Here question, whether is necessary to have two realizations of the RPC using XML? I think that it is not profits integration and compatibility. It seems to me that it is necessary to seek cooperation between developers for establishing of the trade-off decision. -- Best regards, Timur mailto:Timur@niist.ntu-kpi.kiev.ua