There is described a method for converting the wavelength of a pulsed optical signal. An input pulsed signal containing information and having an input wavelength is buffering by propagating the input pulsed signal in a closed-loop optical regenerative cavity. The propagation comprises converting the input pulsed signal at the input wavelength to a buffer pulsed signal at an adjustable wavelength and propagating the buffer pulsed signal within the cavity. The adjustable wavelength is set to a buffer wavelength different from the output wavelength and the buffer pulsed signal contains the information encoded in the input pulsed signal. The output wavelength is determined from the information encoded in the input pulsed signal. Upon determination of the output wavelength, the adjustable wavelength of the buffer pulsed signal is set to the output wavelength in order to; outputting the buffer pulsed signal at the output wavelength from the cavity.