Grammel, Gert (Alcatel-Lucent, Germany)
Building networks have for a long time been based on electrical switching technologies and dumb optical fiber interconnect. However with optical switching technology new networking capabilities have evolved that offer lower cost per bit and better economy of scale. On the other side, maintenance and survivability of such networks is impacted by the nature of optical technology. This requires a new approach to control networks that are based on Next Generation WDM comprising optical and electrical switching. In the past, transport networks have been built considering strict layering inside a single technology like SDH-Higher Order and SDH-Lower Order switching. Now the new networking paradigm is based on a hybrid technology that correlates information available on electrical and optical switching functions to compensate for the lack of information that can be derived from a wavelength along the route. This correlation is provided by a multi-layer control plane that allows to operate the WDM network as if it would be a network based on a dual layer electrical switching technology thereby saving OPEX by integration.