On the fly all-optical packet switching based on hybrid WDM/OCDMA labeling scheme

Abstract

We introduce a novel design of an all-optical packet routing node that allows for the selection and forwarding of optical packets based on the routing information contained in hybrid wavelength division multiplexing/optical code division multiple access (WDM/OCDMA) labels. A stripping paradigm of optical code-label is adopted. The router is built around an optical-code gate that consists in an optical flip–flop controlled by two fiber Bragg grating correlators and is combined with a Mach–Zehnder interferometer (MZI)-based forwarding gate. We experimentally verify the proof-of-principle operation of the proposed self-routing node under NRZ and OCDMA packet traffic conditions. The successful switching of elastic NRZ payload at 40Gb/s controlled by DS-OCDMA coded labels and the forwarding operation of encoded data using EQC codes are presented. Proper auto-correlation functions are obtained with higher than 8.1dB contrast ratio, suitable to efficiently trigger the latching device with a contrast ratio of 11.6dB and switching times below 3.8ns. Error-free operation is achieved with 1.5dB penalty for 40Gb/s NRZ data and with 2.1dB penalty for DS-OCDMA packets. The scheme can further be applied to large-scale optical packet switching networks by exploiting efficient optical coders allocated at different WDM channels.