For the first time, we propose a novel BER estimation algorithm for 8PSK signal, the idea of which is also applicable to
other multi-dimensional and multi-level modulation formats. And a 2 × 4 orthogonal optical label swapping based on
120Gb/s 8PSK payload and 78Mb/s ASK label by using optical switching devices is demonstrated. Through numerical
simulations under different circumstances, we get some orthogonal label switching network's characteristics by
analyzing the receiver BER utilizing the new BER algorithm, such as that different combination of label will have a
different impact on the transmission performance of the packets. In addition, by changing the receiver optical power,
transmitter optical power and optical power launched into the fiber, we get the system's receiver sensitivity, the optimum
transmitter power and optimum optical power injected into the fiber, which will be a reference for the actual systems'