tation of the typology of possible routers and OXCs interfaces by defining standard transport formats. To allow conveying into the network whatever data format through transparency would be a disaster from the monitoring point of view and would complicate a lot the network software that should be ready to deal with one among a set of different formats. Thus, today, format and bit rate transparency appears less an advantage with respect to the early 1990s. All the aforementioned reasons have up to now stopped the development of the optical transparent network and have contributed to convincing a large number of telecom play- ers that this deployment will never happen. Even if the market evolution seems against the transparent network, this technology has still a card to play and considering the strong relevance that environmental issues are also taking in the field of telecommunications, this could be the winning card. As a matter of fact, even if electronics has taken huge strides ahead, optical components still have a much smaller power consumption. If power consumption issues become one of the main drivers of the network and if governments introduce green contribution for carriers that demonstrate less power consumption and a higher taxation for carriers con- suming too much power, transparent optical networks could become again an interesting possibility. 10.4 Transparent Optical Packet Network (T-OPN) Not long after the success of the T-OTN idea, at least at the research level, another even more fascinating idea was launched. In the mid-1990s "packet switching" was mainly ATM, though the success of IP was announced by the commencement of the penetration of internet both in business practice and in private homes. Next Generation Networking: Enabling Technologies, Architectures, and Performances Routing and forwarding table Header Switch processing manager FIGURE 10.35 Input queues Output queues Optical packet switch architecture. In that situation, the idea of a packet optical transparent network was launched,