The need to establish wavelength-routed connections in a service-differentiated fash ion is becoming increasingly important due to a variety of candidate client networks (e. g. IP, SDH/SONET, ATM) and the requirements for Quality-of-Service (QoS) de livery within transport layers. Up until now, the criteria for optical network design and operation have usually been considered independently of the higher-layer client signals (users), i. e. without taking into account particular requirements or constraints originating from the users' differentiation. Wavelength routing for multi-service net...