Minimizing network bandwidth under latency constraints: The single node case

Datacenters have become a significant source of traffic, much of which is carried over private networks. The operators of those networks commonly have access to detailed traffic profiles and performance goals, which they seek to meet as efficiently as possible. Of interest are solutions for offering latency guarantees while minimizing the required network bandwidth. Of particular interest is the extent to which traffic (re)shaping can be of benefit. The paper focuses on the most basic network configuration, namely, a single node, single link network, with extensions to more general, multi-node networks discussed in a companion paper. The main results are in the form of optimal solutions for different types of schedulers of varying complexity, and therefore cost. The results demonstrate how judicious traffic shaping can help lower complexity schedulers reduce the bandwidth they require, often performing as well as more complex ones.