INTERFACCIA DI CONTROLLO E COMMUTAZIONE DI ETICHETTA PER COMMUTAZIONE VELOCE DI PACCHETTO ASINCRONA

A label-switching and control interface for asynchronous fast-packet switching consisting of a set of label-switching and cell-processing units controlled by a suitable control unit; said units operate at each multiplex level in real time thanks to a microprogrammed logic requiring the control processor intervention only at the connection set-up/release. Said units implement the low levels of the flow control algorithms necessary to conveniently exploit the advantages of said techniques. The label becomes indicative of a virtual circuit which is allotted only locally to the call, annulling thus the necessity of very extensive labels, while the parameters which characterize the connection which uses a particular label are stored in the unit itself. Each unit switches the label characterizing the connection on the node input multiplex, with that whereby it is characterized on the output multiplex and at the same time associates, with each cell, the information necessary to multiplex switching which is then carried out in a self-routing network; the cells processed in this way by each unit of the set are statistically multiplexed ifl an asynchronous way and sent to a connection network termination. Such a termination serves more asynchronous multiplexes, which can be at different frequency from each other and more particulary it is worth noticing that each label switching unit hasn't its own operating frequency, but automatically takes up that of the asynchronous multiplex it is connected to.