P-FatTree: A Multi-channel Datacenter Network Topology

The bandwidth and latency requirements of next-generation datacenter networks stress the limits of CMOS manufacturing. A key trend in their design will be a move from single-channel links and switches to multi-channel links and switches. Today's network topologies erase this distinction, providing the illusion of a unified network fabric. In this work we propose P-FatTree, which is a FatTree topology designed specifically for the future multi-channel reality. P-FatTree requires fewer switch chips and as a result has lower cost, power consumption, and latency than existing approaches. Furthermore, by embracing the parallel nature of the network itself, it enables compelling new ways to better manage and deliver application traffic.