The Role of Signaling in Quality of Service Enabled Networks

In this paper we identify the common building blocks that enable some networks to provide better than best-eeort transfer guarantees to the traac they carry. We consider the role signaling plays in such a network and argue in favor of: pinned routes, with a highly eecient pinning process, to improve network stability and to ease the task of maintaining Quality of Service (QoS) guarantees in the face of changing network characteristics, including failures. the use of broad QoS classes to determine the path that a particular ow should follow through the network. providing the exibility of specifying the detailed QoS for the ow, if needed, at any arbitrary time during the life of the ow. We conclude that a exible signaling architecture is an essential enabling component of any QoS aware network. We present an overview of the design and implementation of UNITE, as an example of a signaling architecture that embodies these attributes. More generally, we consider the relationship between QoS related signaling and other protocols and mechanisms that may form part of a an overall QoS enabled network and service infrastructure.