Patent ID: 7139277

Claim:
A communications system, for controlling the transport of SONET frames, with a fixed time duration, from a SONET network over a time-driven switching (TDS) network, the system comprising: a Common Time Reference (CTR), divided into a plurality of contiguous time frames (TFs), wherein the time frames have a plurality of predefined time durations; a fractional lambda interface (FLI) for controlling of interfacing of the SONET network with the time-driven switching (TDS) network; wherein a SONET channel is comprised of a contiguous plurality of SONET frames, comprised of a predefined number of lower-rate SONET sub-channels; wherein the predefined number of lower-rate SONET sub-channels are byte interleaved within the SONET frames; wherein the FLI provides means for separating the SONET channel, within the fixed time duration, into a plurality of non-byte interleaved lower-rate SONET sub-channels; wherein each of said plurality of non-byte interleaved lower-rate SONET sub-channels is defined as a part of one of the SONET frames; wherein the FLI provides first means for mapping each of the non-byte interleaved lower-rate SONET sub-channels to selected ones of the TDS network time frames; and wherein the selected ones of the TDS network time frames with the non-byte interleaved lower-rate SONET sub-channels are switched and forwarded responsive to the CTR over the TDS network.