A network apparatus comprising storage units storing configuration information about the network apparatus, an input network interface to at least one network physical line, at least one processor receiving network data from said network interface, processing said data, storing information about said network data in said storage units, storing said data as formatted data units in said storage units, a first bus interface to two bus connections, a first hardware component reading said configuration information and said information about data stored in said storing units and steering said formatted data units stored in said storage units to at least one of the two bus connections of said first bus interface, a second bus interface to two bus connections, an output network interface to at least one network physical line, a second hardware component reading formatted data units arriving on at least one of the two bus connections of said second bus interface and storing said formatted data units in said storage units, said at least one processor reading said formatted data units from said storage units, processing them and sending them as network data to at least one network physical line through said output network interface. On the basis of this network processor, it is possible to build switching systems by adding one network processor and at least one switch; it is also possible to build double density blades attached to two redundant switch fabrics which can also be accessed concurrently.