Expeditus
Peng Wang, Hong Li Xu, Zhixiong Niu, Dongsu Han, Yongqiang Xiong · 2016
Data center networks often use multi-rooted Clos topologies to provide a large number of equal cost paths between two hosts. Thus, load balancing traffic among the paths is important for high performance and low latency. However, it is well known that ECMP---the de facto load balancing scheme---performs poorly in data center networks. The main culprit of ECMP's problems is its congestion agnostic nature, which fundamentally limits its ability to deal with network dynamics.