Optical power control in translucent flexible optical networks with GMPLS control plane

The continuously increasing traffic of Internet services (cloud services, video streaming, social networks, and recently, Internet of Things services) is leading to huge traffic growth in core optical networks. This traffic evolution is pushing network operators to efficiently exploit their infrastructures in order to postpone, as much as possible, the expensive deployment of new infrastructures. In this respect, the migration from fixed-to flex-grid optical networks was triggered in order to efficiently use optical network capacity, taking benefits from the improved spectral efficiency of flexible transponders. In our previous work [J. Opt. Commun. Netw., vol. 8, no. 8, p. 553, Aug. 2016], we demonstrated that migrating towards flexible networks while keeping in use existing optical amplifiers will cause a power saturation problem over highly loaded links due to the increase in the number of optical channels. To overcome this problem, we proposed in that work a power adaptation process that consists of converting transmission performance margins into optical power attenuation over optical links. However, the realized work considered only a transparent optical network controlled by the generalized multiprotocol label switching (GMPLS) protocol suite. In this paper, we consider the case of a translucent optical network where optical regeneration is required, and thus, the power adaptation process is adapted to this kind of network. A new routing algorithm and protocol extensions are proposed to take into account power and regeneration information in the GMPLS control plane of translucent networks.