Multilayer Optimization of Inverse-Multiplexed 100 Gb/s Ethernet Services over Optical Transport Networks

Stimulated by the remarkable packet traffic growth, the transport of 100 Gb/s Ethernet (100-GbE) services is to become a reality in a near future. To provide a smooth and cost- efficient network evolution, inverse-multiplexing techniques can be employed to carry the high-capacity data streams. In this context, the virtual concatenation (VCAT) protocol, available in optical transport network (OTN) systems, represents the most adequate solution to decompose the 100-GbE signal into logical containers of 10 Gb/s and 40 Gb/s. With VCAT, each container can be independently routed throughout the network under several distribution paradigms, such as the classical single-path and multipath schemes, and the alternative degraded-service approach. In the network architecture considered, each routing path is required to be transmitted over an optical channel at the underlying WDM layer. Hence, in this work, we provide an optimization framework for solving the resource provisioning problem for 100-GbE at both OTN and WDM layers. Linear programming based heuristics are proposed for routing the containers and dimension the capacity required at the OTN level. In particular, solutions for single-path, multipath, and degraded-service routing are described and evaluated in a reference network topology. The optimization procedures are also extended to resolve the wavelength assignment problem at the physical WDM layer. With this optimized multilayer architecture, the capacity gains resulting from the adoption of multipath strategies over single-path are properly evaluated and demonstrated. In addition, it is shown that the implications of using diverse-routing over the WDM layer have a minor impact in the capacity savings.