Patent ID: 7356025
Filing Date: 2008-04-08
Classification: H04Q

Abstract:
1. An apparatus for switching data between a first set of bitstreams and a second set of bitstreams, each of said bitstreams being divided into recurring frames and each of said recurring frames being divided into time slots, comprising: a first set of switching elements, at least one intermediate set of switching elements, and a last set of switching elements, wherein each switching element comprises a number of input ports and a number of output ports, and a control unit for controlling the allocation of bandwidth in outgoing bitstreams, referring to the output ports of the switching elements, said control unit being operatively connected to each of the switching elements, wherein the input ports of said first set of switching elements are arranged to receive said first set of bitstreams and the output ports of each switching element in said first set of switching elements are operatively connected to input ports of more than one switching element in one of said at least one intermediate set of switching elements, wherein the input ports of each switching element of said last set of switching elements are operatively connected to output ports of more than one switching element in one of said at least one intermediate set of switching elements and the output ports of said last set of switching elements are arranged to provide said second set of bitstreams, wherein each switching element is arranged so that it provides for both time and space switching of data from incoming bitstreams, referring to the input ports of each said switching element, to outgoing bitstreams, referring to the output ports of each said switching element, and wherein the control unit determines whether there is one switching element in said intermediate set of switching elements, for which there is enough available bandwidth to carry a channel in bitstreams from said one switching element to the switching elements in said last set of switching elements, and determines, in the case where there is one such switching element, whether there is enough available bandwidth to carry the channel in one bitstream from a switching element of said first set of switching elements to said one switching element.