The capacity of metro optical networks is being constrained by the rollout of high-bandwidth access networks. Agile optical networking has been touted as the architecture of choice to mitigate the middle mile "bottleneck".

This article, by Ken Davison who is vice-president for marketing at Meriton Networks, in optics.org does a particularly good job of defining what agile optical networking means and analogies are provided with the M25 orbital motorway. Further, enabling technologies (WSS ROADM, CWDM, multidegree wavelength and sub-wavelength switching) are discussed.