Network Processors: A Practical Approach for Achieving Wire-Speed Packet Processing in the Emerging Optical Backbone Networks

In this paper, the wire-speed packet processing issue is studied for optical packet/burst switching (OPS/OBS) switching nodes as well as for wavelength-routing (WR) switching nodes. Some assumptions are made to obtain simple estimates of the requirements in terms of forwarding events per second. This is compared with the packet processing performance of electronic devices which implement this type of tasks. Specially, the state-of-the-art in network processor (NP) technology is examined. NPs seem to offer the best flexibility/performance trade-off. Our results reveal that in the OPS/OBS alternatives, wire-speed packet processing cannot be considered a challenge. Furthermore, it is not dependent on the binary rate of packet payload. In wavelength routing networks, the reduction in electronic processing provided by transparent lightpath switching is considered. Nevertheless, this alternative reduces, but does not eliminate, the packet-processing bottleneck. In the authors' opinion this situation will promote OPS/OBS technologies.