Four variants of the optical data center network architecture (DCN1 - DCN4) based on optical circuit switching and elastic optical switching elements are proposed. For each variant theoretical limits for non-blocking operation have been derived and proved. The proposed networks are also compared in terms of the required number of switching elements. Our results show that variant DCN1 is more appropriate for very small data centers with tens of racks with servers, while variant DCN4 requires much fewer switching elements in data centers with hundreds or thousands of such racks.

In this paper, we introduce a new multiplane optical switching fabric structure based on a baseline type switching network. The new structure is built from symmetrical and asymmetrical optical switching elements. This new architecture can be extended to structures of greater size (it means capacity as a number of inputs and outputs). To compare different types of switching architectures, we define the cost of an appropriate structure as the number of its passive and active optical elements. Generally, structure with smallest number of these elements constitutes a cheaper solution. We also introduce a strict-sense nonblocking conditions for the proposed multiplane structure and compare them with an optical baseline multiplane switching networks of the same capacity. We show that for most capacities of the switching network, the new multiplane architecture is a cheaper solution than the multiplane baseline network even when the number of planes in the new architecture is greater than the number of one planes in the baseline structure — cost of the whole new structure expressed as the number of passive and active optical elements is fewer than baseline network of the same capacity.

In this article, we introduce a new space-division optical switching fabric architecture based on baseline switching networks. The new structure is built from optical switching elements (OSE) 2 × 2, 3 × 3, 2 × 3, and 3 × 2. The new structure is called the log2N-1 switching network and consists of fewer numbers of active and passive optical elements than traditional baseline switching networks composed of symmetrical OSEs. In the paper, we investigate space-division multiplane strict-sense and rearrangeable log2N-1 nonblocking switching networks and compare these with space-division multiplane baseline switching networks. The new structure has lower cost than other architectures for strict-sense nonblocking (SSNB) conditions and for rearrangeable (RNB) networks with odd number of stages. For RNB networks, when the number of stages is even, the cost of the multiplane log2N-1 optical switching network is equal to or higher than traditional networks.

In this paper, we propose the new architecture of the optical switching fabric which is based on the baseline switching network. Traditional baseline switching networks are composed of 2 × 2 (or d × d) switches. The new architecture considered in this paper is constructed from 2 × 2, 3 × 3, 2 × 3 and 3 × 2 switching elements. We show, that the proposed architecture requires less crosspoints than the traditional baseline architecture. We assumed an optical application, where semiconductor optical amplifiers are used as the optical switching elements. The proposed structure requires less number of active elements as well as passive optical splitters and combiners than the traditional baseline switching fabric. It also contains one stage fewer than the banyan network (therefore we called it the log2N - 1 switching fabric), which results in lower signal losses, distortions, and crosstalk.