I. Introduction
Optical technologies advances in transport networks provide the Internet with the bandwidth required by data-intensive applications. In addition, the Control Plane (CP) functionality provides transport networks with a fast and dynamic response to bandwidth requirements of client networks. More recently, customers require operators to design enhancement of transport networks such that they can offer both executive and informative services directly to individual qualified users' applications [1]. For example an application for data storage may request a transport network to provide an ad-hoc qualified point-to-point connection on a virtual private network with guaranteed QoS, instead of using a best-effort connectivity service on the public Internet. To this purpose, applications should be enabled to directly trigger the provisioning of a network service, (e.g. a simple bandwidth allocation, a virtual topology set-up), without dealing with technological details of the transport devices. This general requirement provides the motivations for investigating a new conceptual interface between the applications and the transport network and the way to support a direct service invocation by applications.