Overview of the JSON-RPC mechanism.
JSON-RPC is a simple RPC (Remote Procedure Call) mechanism, similar to XML-RPC.
Unlike XML-RPC which is a client-server protocol, JSON-RPC is a peer-to-peer protocol.
JSON-RPC defines the three message types Request, Response and Notification. There is no direct mapping of JSON-RPC message to HTTP request. HTTP or plain TCP are merely transport protocols that carry JSON-RPC messages.
JSON-RPC is a simple protocol and therefore lacks most of the features that big web services like SOAP/WSDL and the WS-* standards provide. JSON-RPC may be suited for web service applications with the need for bidirectional interaction (peer2peer), but where the complexity of SOAP is not required.