Simple Provisioning, Complex Consolidation - A Pragmatic Step Towards a New Optical Layer

The permanently increasing data traffic of IP services and broadband applications has become the largest traffic component in transport networks. The requirements of the dominant IP-client result in major changes of the architecture and in the networking paradigm of the optical layer. Due to these changes fast provisioning capabilities enabled by signalling intelligence and automated switching flexibility are becoming fundamental features of optical networks, thus these network gradually becomes a powerful transport layer for next generation networks. To improve the capacity efficiency of provisioning oriented networks consolidation phases should be applied time by time. Basically, consolidation is a network rearrangement of a limited extent to re-optimize the path selection and wavelength assignment resulted in on-line processes. The current paper extends the basic consolidation approach, since not only the routing and wavelength assignment problem is reconsidered during the consolidation, but the resilience architecture, as well. Therefore, a provisioning-consolidation based process is proposed to accommodate optical channel requests with different availability requirements in combined simple distributed on-line and in more complex off-line design based centralized processes. Numerical examples are presented to illustrate the efficiency of the proposed approach