Infrastructure Cost Evaluation of Intra-Data Centre Networks

In this paper we present an evaluation of the infrastructure costs of five intra-data centre network architectures, namely, leaf-spine, fat-tree, hybrid fat-tree, Facebook 4-Post and a new Facebook fabric. A bottom-up cost calculation approach is used whereby all network architectures are designed so as to meet target oversubscription ratios. From the resulting designs the infrastructure costs are calculated as the sum of the switching and cabling costs. The results show that the leaf-spine network provides the lowest costs. Besides, for all architectures, the leaf (or top of the rack) switches are the dominant cost drivers.