Communication middleware such as MuniCluster provides highlevel communication mechanisms for networked applications through hiding the low-level communication details from the applications. The MuniCluster model provides mechanisms to enhance the network performance properties through message separations and parallel transfer. However, the configurations of such its services require various measurements and setups to efficiently utilize the availability of the multiple network interfaces. In this paper we introduce and evaluate a self-configuring model that allows applications to transparently utilize the existence of multiple network interfaces and networks. Here we present enhancements to the MuniCluster model by adding the selfconfiguration mechanism. Using network resource discovery and deciding on how to efficiently utilize the multiple networks, the model enhances overall communications performance. The proposed techniques deal with the heterogeneity of interfaces and networks t...