Future computer networks must be more flexible and faster then today. Active network paradigm is the way how to add flexibility to networks. During the last five years, a number of models for active networks realization were presented. In active networks, the concept of network as a distributed programmed facility is developed. This concept makes possible new applications and special services. Active network models are described and our active network model is described in more detail. We discus applications which need special network features and the position active routers and switches have in network infrastructure in order to satisfy these demands. An application which supports collaborative work, requiring data, audio and video streams to be transferred through the network is used to demonstrate how active network element can process dataflows with specific features in both uni- and multicast environments. An overly of active network elements placed in particular points of the non-intelligent high speed network is presented as a model which supports both the intelligence and high throughput without need of specialized costly hardware support
