Tlme to Download a 10 Mb Flle Uslng Networks with Varlous Bandwidths 50 45 40 35 30 Minutes 25 20 15 10 5 。 28.8 Kbps 56.0 Kbps (x2 128. Kbps (Bundled 1.5 Mbps (T1) 6.0 Mbps (T2). 10 Mbps (Ethemet) Analog) ISDN) Network Bandwidths
Figure 4. Time to Download a 10 Mb File with Various Network Bandwidths
According to analysts at Gartner Group and analysts at the Yankee Group, about 65% of all Intemet users are expected to be surfing with 28.8 Kbps modems through the year 2000[10]. This means that the majority of Intemet Web users are not able to access large files, such as video and audio recordings, at a satisfactory speed. Even when accessing files through using a Tl line, which is unaffordable in the average household, the data transmission speed, with the aforemen-tioned multiple factors being involved, can only roughly be an equivalent to a lX CD-ROM drive,
which is 150 Kpbs[II].Due to the low Web
(frames per second) to lOfps shown in a tiny screen can be seen on the Web. As to static graph-ics, a picture as small as 35K takes 31 seconds to download at 14.4 Kbps or 15 second at 28.8
Kbps[1 月.
However, the good news is that new tech-nologies are being developed to enhance Web speeds. Primary rate ISDN, for ex訂nple ， allows a data transfer rate of up to 2 Mb阱， making it pos-sible to transmit large data volumes within a reasonable time. With this technology, the trans-mission of 的oMb for a CD-ROM would require about 47 minutes. In addition, a primary rate speed, it is not unusual that only video with 5fps ISDN connection can be used for video
