High-Radix Nonblocking Integrated Optical Switching Fabric for Data Center

To accomplish high-bandwidth and low-latency communications among tens or even hundreds of nodes with low power consumption, dual radial and angular grating optical network (DRAGON), a new integrated high-radix strictly nonblocking optical switching fabric, is proposed in this paper. The topology and routing algorithms of DRAGON are discussed, and a formal proof for the strictly nonblocking property is presented. With the loss model developed, we show DRAGON has significantly lower worst-case loss as well as average loss compared with other widely studied integrated nonblocking switching fabrics. In addition, our crosstalk analysis also suggests a lower crosstalk of DRAGON. For example, for 32 wavelength division multiplexing channels, both the worst-case loss and average loss of
${\text{180}}\times {\text{180}}$
DRAGON are around 20 dB lower than crossbar of the same size, and 28 dB lower than
${\text{128}}\times {\text{128}}$
Beneš. Furthermore, due to the strictly nonblocking property, DRAGON has advantages of smaller communication latency and larger throughput compared with Beneš switching fabric.