Optical data centers router design with fiber delay lines and negative acknowledgement

Abstract EN

Optical packet switch /optical interconnect will be an integral part of high speed switching and datacenter applications.

in recent past arrayed waveguide grating (AWG) based designs have shown promising solutions for contention resolution and packet routing.

most of the designs take the advantage of wavelength parallelism and wavelength-based routing nature of awg.

in general, two classes of design have emerged : buffer-less and with buffer.

in recent past the concept of all-optical negative acknowledgement (AO-NACK) is introduced in case of buffer-less design.

here, in case of dropping of packet a negative acknowledgement is sent back to the sender to retransmit the packet.

the drawback of the scheme is that the numbers of retransmitted packets are huge in buffer-less design.

in this paper, a buffer-based design is presented where both buffer and negative acknowledgement areutilized to reduce the number of transmitted packets to 3000 times compared with buffer-less design, in case of transmission of 10 packets moreover, negative acknowledgement hardware design is simplified significantly.