With the advent of flexgrid optical networks, the rigid wavelength-division multiplexing (WDM) technology\udwill be enhanced by providing better spectrum efficiency and flexibility. In those future flexible optical\udnetworks, optical connections (lightpaths) can allocate a flexible number of spectrum slices, also known as\udfrequency slots, so to match better with its requested bitrate. In this paper, we propose to take advantage of this\udflexible spectrum allocation in recovery mechanisms to be triggered when a failure occurs to provide recovery of\udpart of the requested bitrate, i.e. the allocated spectrum by backup lightpaths could be lower than that of the\udworking lightpaths provided that client service level agreements are fulfilled. This reduction in the recovered\udbitrate (bitrate squeezing) allows optimizing the use of network capacity. We propose path-based recovery\udalternatives, based on protection and restoration, specially designed for flexgrid networks. The performance of\udthe proposed recovery mechanisms is exhaustively evaluated on a national reference network
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