Patent ID: 6449288
Filing Date: 2002-09-10
Classification: H04L,H04M

Abstract:
A bi-level framer for framing data transmitted over a line at a low line rate, the bi-level framer comprising:mux-framing means, receiving user payload bytes and a sync byte, for generating mux data frames by appending Np user payload bytes to the sync byte; correction-byte means, receiving a plurality of S/M of the mux data frames from the mux-framing means, for generating a plurality of Ri forward-error correction FEC bytes; symbol-framing means, receiving the plurality of S/M mux data frames from the muxframing means and receiving the plurality of Ri FEC bytes from the correction-byte means, for generating a plurality of S symbol frames from the S/M mux data frames and the Ri FEC bytes; and a symbol generator, responsive to a system clock, for generating a symbol for transmission over the line for each symbol frame from the symbol-framing means; wherein M is an efficiency factor that is 1 when transmitting at a high line rate above the low line rate, but a positive integer greater than one when transmitting at the low line rate, whereby one symbol is transmitted for each mux data frame at the high line rate, but M symbols are transmitted for each mux data frame at the low line rate.