Embedded Peer-to-Peer Systems (EP2P) represent a new challenge in the development of software for distributed systems. The main objective of the SMEPP (Secure Middleware for Embedded Peer-to-Peer Systems) project is to develop a new middleware, based on a new network centric abstract model, specially designed for the above described systems, and trying to overcome the main problems of the currently existing domain specific middleware proposals. This paper presents a SMEPP Middleware component-based simulation tool. The main objective of developing this simulator is to provide a tool to enable the testing of the service model proposed for the middleware and to provide a framework to test different middleware design choices. Simulations will help us to make future decisions. Simulating SMEPP applications, that is, applications running on the SMEPP middleware and based on the API that it offers, help us to make decisions about the most requirement-satisfactory way of constructing the middleware. The simulated middleware API component represents a first approach to middleware design, and introduces some of the architectural issues that must to be solved in the near future.