Intra-Datacenter Network Architectures

This Handbook chapter provides an overview of existing interconnection topologies and architectures for large-scale cloud computing systems. We discuss (a) tree-based solutions (also referred to as indirect topologies in this chapter), largely adopted in most of today's data center systems, as well as (b) directly connected topologies, such as full mesh (all-to-all), flattened butterfly, and HyperX. This chapter also touches upon some emerging interconnect solutions enabled by recent advances in photonic integrated technologies and switches, while more details about these aspects can be found in the Handbook Chaps. 21, 24, and 25.