  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.
