Please contact NTT-AT for maintaining an optical network system without poor connection or burnout accidents. The power of optical transmission becomes higher due to the increase of transmission data in an optical network. If there is a contamination or defect in the shape at the connection point of an optical network, the high power optical energy causes burnout and can lead to a serious accident of communication error due to the failure in damaged network devices in a network system. NTT-AT provides the connector cleaners and the polishers that are designed and manufactured with the deepest consideration and from actual feedback from communication construction sites - those products protect leading-edge optical networks. The optical network supports rapidly increasing communication throughout the world. And architecture and maintaining tools that support the optical network are NTT-AT's products.