Rate-Controlled Service Disciplines

               Hui Zhang and Domenico Ferrari

We propose a class of non-work-conserving service disciplines, 
called the Rate-Controlled Service Disciplines. When coupled with
suitable admission control algorithms, Rate-Controlled Service Disciplines
can provide end-to-end deterministic and statistical performance guarantees 
on a per-connection basis in an arbitrary topology packet-switching network. 
The key feature of a rate-controlled service discipline is the separation 
of the server into two components: a rate-controller and a scheduler. 
This separation makes it possible to obtain end-to-end performance 
characteristics by applying single node analysis at each switch.
It also has several other distinct advantages: it decouples the allocation 
of bandwidths and delay bounds, uniformly distributes the allocation of 
buffer space inside the network to prevent packet loss, and allows arbitrary 
combinations of rate-control policies and packet scheduling policies. 
Rate-controlled service disciplines provide a general framework within which 
most of the existing non-work-conserving disciplines can be naturally 
expressed. One discipline in this class, called Rate-Controlled
Static Priority  (RCSP), is particularly suitable for providing performance 
guarantees in high speed networks. It achieves simplicity of implementation 
as well as flexibility in the  allocation of bandwidths and delay bounds 
to different connections.