Network file for ISDN

The necessity of file-storage systems for network systems such as ISDN (integrated services digital network) and B-ISDN (broadband ISDN) is discussed. The stored information has a wide range of characteristics depending on the storage medium and it is accessed and transmitted through heterogeneous networks. Since visual services will increase with the progress of network systems, the file-storage system must provide large capacity, low storage cost, and high transfer rate. In ISDN and B-ISDN, these requirements will be met by optical-disk storage systems. In the future, the file-storage system will need to provide a huge storage capacity and an ultra-high data transfer rate sufficient for high-quality visual services at a low cost. This will require innovative technologies in memory devices and materials to surpass the real recording-density limits of present technologies. >