R. Mehmood et al. (Eds.): EuropeComm 2009, LNICST 16, pp. 74–82, 2009. © Institute for Computer Science, Social-Informatics and Telecommunications Engineering 2009 RSVP-TE Based Impairments Collection Mechanism in DWDM Network Marco Anisetti 1 , Valerio Bellandi 1 , Roberto Cassata 2 , Ernesto Damiani 1 , and Zafar Ali 2 1 Università degli studi di Milano, Department of Information Technology, Italy {marco.anisetti,valerio.bellandi,ernesto.damiani}@unimi.it 2 Cisco System, USA Abstract. The problem of path validation of a pure light-path in a Dense Wavelength Division Multiplexing (DWDM) optical network requires the transmission of optical impairments related parameters along the provisioned route. In this paper we propose an RSVP-TE based mechanism to collect and evaluate optical impairments measured over optical nodes along the light-path. Keywords: DWDM, Impairments, RSVP-TE. 1 Introduction With the development of dense wavelength-division multiplexing (DWDM), optical switches have become the key device in today’s optical networks. DWDM- based meshed networks will require novel techniques of optical protection, going well be- yond traditional techniques based upon redundancy at the system, card, or fiber level. It is widely acknowledged that in the next generation of optical networks (wavelength switched optical networks), redundancy will be wavelength-based. In other words, the optical infrastructure will be able to react to faults by switching wavelengths or fibers, routing connections in real time through the networks of different vendors on the optical layer. These switching capabilities will rely on a software layer implementing routing and signaling protocols. Several mechanisms for link management aimed at all-optical networks. The Generalized Multi-protocol Label Switching (GMPLS), supports a number of mechanisms for dynamically allocating resources, providing fault protection and restoration techniques. From its beginning Generalized Multi-Protocol Label Switch- ing (GMPLS) was intended to control wavelength switched optical networks (WSON [1]) with the GMPLS architecture document [2] explicitly mentioning both wave- length and waveband switching and equating wavelengths (lambdas) with GMPLS labels. Unfortunately GMPLS protocol suite cannot be fully exploited in photonic DWDM networks or WSON. A major problem is due to purely optical interfaces, where there is no electro-optical conversion. Nevertheless the control of WSON via GMPLS is currently under study, a further effect need to be taken into account also for the actual DWDM optical networks.