Traffic management and network planning for optical IP over WDM networks

Several aspects have motivated the current interest of the Internet community for optical technologies. The first of these motivations is related to the necessity of a higher network capacity facing the rapid growth of the Internet traffic. Dense wavelength division multiplexing (DWDM) is today a simple and cost effective solution to this difficulty. The second motivation refers to the necessity of introducing quality of service (QoS) in IP networks in order to facilitate voice, video and data services integration. Multi-Protocol Label Switching (MPLS) is today considered as the most promising technique to introduce such QoS. The feasibility of optical switches and of optical routers has been demonstrated in various ACTS research programs. Thanks to these advancements, an extension of MPLS to optical switching fabrics is under study within various standardization bodies under the name of Generalized MPLS (GMPLS). In a first step, this paper aims at presenting the various approaches considered by the standardization bodies for new generation IP networks and optical networks. The overlay and peer-to-peer approaches to combine these two types of technologies are commented on, a particular interest being dedicated to the ITU-T vision with the optical transport network (OTN) definition. The rest of the paper focuses on the very open problems of traffic management and network planning in all-optical IP networks.