Primary theme of presentation at ISS

The conceptual diagram (Fig. 1) explaining that lines within and outside offices should be separated is the section where the primary theme is indicated most clearly among the materials presented.

Fig. 1 Excerpt from the ISS lecturing materials
Diagram explaining that lines within and outside the office should be separated. IASVC within the diagram is the VoIP device.

At any rate, what we were focusing on was establishment of voice quality. As described many times in this series, I believe that establishment of voice quality is the major key to the dissemination of IP telephony, and our concept was based on providing maximum voice quality by firmly grasping the environment. At the time, LAN had become popular within corporate offices and network environments with speed of 10M ~ 100Mbps were becoming more common. Although many LAN used hubs, we paid close attention to the trend of LAN switches. (Port unit cost made a steep drop when entering 1997 and use of broadband within offices increased rapidly.)

Since broadband cannot be established for dedicated lines among offices due to the high cost, there is the need to establish quality based on narrow band. Hence, I protested that technical viewpoints for establishing voice quality was totally different and that the two should not be considered based on the same grounds. They must be viewed upon from their respective viewpoints and efforts are to be made for the optimal method of securing quality in each environment.

For example, switches exchanging information within an office are LAN switches and thus efforts on a MAC layer are possible. Since use of a broadband environment is possible, we simply placed emphasis on "how accurately waves are sent" by passing signals uncompressed, regardless of whether the signal is a fax, modem or voice. And such technical methods were introduced in the presentation.