Heterogeneous network testbed for multimedia service in NTT

Since April 1991, NTT has been conducting comprehensive experiments related to visual, intelligent and personal communication services (VI&P), NTT's service vision for the 21st. century, at its company's laboratories. Presently, the N-ISDN, broadband ATM network and high speed-computer communication network connects two NTT R&D centers, and optical subscriber systems that have been introduced at the Yokosuka R&D center and various applications and service experiments are being carried out. The paper first describes the concepts that were used to construct the testbed and conduct the experiments; then the total system configuration and some results that were obtained through both network and service system experiments; and finally future plans to make a heterogeneous network testbed for multimedia services based on experience from these results.