An optical transport platform

Today's transport networks are based on electronic SDH cross-connects (XCs) and high-capacity single carrier opto-electronic transmission line systems supporting various switched platforms ATM, SMDS, frame relay etc. Tomorrow, it will be feasible and cost-effective to build the transport infrastructure using layers of electronic and all optical cross-connects, interconnected with very-high capacity multiple wavelength (WDM) carrier transmission systems with significant capital cost savings. A managed optical platform will also simplify resilience management of breaks in optical cables allowing rapid reconfiguration of routes using optical XCs without the need to reconfigure large numbers of 150 Mbs (AU4) and 2 Mbs. Consider for example the current SDH layer. All traffic entering an SDH node is processed electronically whereas much of it could pass through without grooming or switching at this level. For example an optical XC (or OADM) could route tandem traffic cost effectively at N/spl times/155 Mbs whilst also providing additional resilience options. Hence there is an opportunity to fundamentally re-address both PDH and SDH resilience strategies whilst utilising the currently installed fibre infrastructure for future growth with WDM as the enabling technology.