Dynamically reconfigurable all-optical correlators to support ultra-fast internet routing

Optical correlator employing opto‐VLSI processing

“…However, false pattern recognition can be avoided by adding a second correlator that is configured in complement to the first correlator, as reported by Hauer et al [6].…”

“…Recently, an array of fibre Bragg gratings (FBG) in conjunction with a single photodetector have been proposed to construct a fibre-based optical correlator for optical-header recognition [6]. This technique is susceptible to optical interference caused by the detection of the same delayed optical bits using a single photodetector when the coherent time of the optical signal is higher than the bit time delay created by the FBGs.…”

Application of slow light: a DARPA perspective

“…One such device is an optical correlator, 16 which requires a set of delays to correlate the header of an optical packet with a desired address. As shown in Figure 1(b), summing delayed copies of the header will produce a correlation function, however, not necessarily one that lends itself to a simple, robust determination of the header address.…”

Optical header processing in high-speed optical networks

“…Current optical signal processing technologies, however, do not scale well, making it impractical to build a 100,000-entry all-optical look-up table. But in the core network, where routers have only four to eight output ports and only a few hops may be necessary to reach a core access point, it may be possible to determine a packets destination port by looking only a subset of the bits in the destination address 32 . Here we consider, for example, that the AOLS node will be characterized by four input/output fiber ports.…”