Behavior of current communication protocols as well as current and future networked applications is of fundamental importance for technical and commercial success of Mobile Internet. The forthcoming wireless Wide-Area Networks, such as GPRS and UMTS, are quite complex and network operators have a large set of parameters to tune the transfer performance of these networks. In this situation it is of great value to be able to execute practical experiments. The Seawind emulation software introduced in this paper enables measurements of protocol implementations in modeled networking environments. The Seawind software provides a rich set of ways to define transfer characteristics including delays and errors. The software has also means to conduct large sets of experiments in an automatic fashion. In addition, tools of analyzing measurement data has been integrated into the Seawind software.