Construct detailed, essay-format responses to the following prompts, synthesizing information from across the source material.

1. Analyze the evolution from traditional, static TDM-based transport networks to dynamic, reconfigurable optical networks. Discuss the limitations of the former (e.g., inefficiency with bursty data traffic, cost of overprovisioning) and the advantages of the latter, focusing on the roles of WDM, ROADMs, and digital wrappers.
2. Explain the architectural concept of the Optical Transport Network (OTN) as the underlying “network of networks.” Describe how its layered structure is conceptually analogous to SDH, but also detail the significant distinctions arising from its reliance on analog WDM engineering versus digital TDM engineering.
3. Provide a comprehensive overview of the key components that constitute an optical data network. Your answer should detail the function and significance of Transponders, various types of Optical Amplifiers (EDFA, Raman), Multiplexers/Demultiplexers (Prism, Grating, AWG), and the Optical Supervisory Channel (OSC).
4. Discuss the critical importance of survivability in optical networks. Compare and contrast the different approaches to protection and restoration, including the trade-offs between line layer and path layer schemes in terms of cost, complexity, and bandwidth efficiency.
5. Elaborate on the technological advancements embodied by the Reconfigurable Optical Add-drop Multiplexer (ROADM). Explain its core architecture, including the function of the Wavelength Selective Switch (WSS), and define the advanced capabilities described by the terms “Colorless,” “Directionless,” “Contentionless,” and “Gridless.”