Patent ID: 7206323
Filing Date: 2007-04-17
Classification: H04J

Abstract:
1. A line card for use in a node of a network to connect to optical network lines, comprising: an optical interface; a serializer/deserializer (SERDES) configured to operate at a first frequency; and a framer configured to operate at a second frequency, the first frequency being higher than the second frequency, the framer including a digital step up converter to receive data from the SERDES and a digital step down converter to supply data to the SERDES; wherein the step down converter includes a set of input buffers, each input buffer configured to receive a word of nibbles from the framer, the input buffers being loaded one after another, but extraction from each of the input buffers to a multi-stage multiplexer is triggered so long as a non-reset window is preserved; wherein the step up converter includes a set of input buffers and a register array, each input buffer configured to receive a word of nibbles from the register array, the input buffers being loaded one after another, but extraction from the input buffers to a multi-stage multiplexer is triggered so long as a non-reset window is preserved, and wherein the set of input buffers of the step up converter includes 4 input buffers and the set of input buffers of the step down converter includes 4 input buffers; wherein the multi-stage multiplexer of the step down converter is a 5 stage converter.