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240 Chapter 10

3%
Figure 10-2 14.4 or less
Network access 5% 13%
speeds 128 Kbps ISDN other 33%
28.8-33.6 modem
13%
1.544 DS-1
33%
56 Kbps modem

In 1996, a major change began to take shape in the telecommuni-
cations industry. The Incumbent Local Exchange Carriers (ILECs)
and the Competitive Local Exchange Carrier (CLECs) were faced
with the dilemma of satisfying the explosive demand for connections
to the Internet. This, of course, was done initially using dial-up com-
munications. At the time, modem speeds of 14.4 to 56 Kbps were
common and users were happy just to be logged on. However, the
term World Wide Wait began to express the frustration people were
experiencing when they logged on to an Internet Service Provider
(ISP) who had insufficient capacities to satisfy the demand. More-
over, these ISPs were consuming all the bandwidth in the telephone
company’s central office (CO) because the typical user in a telephony
environment talked for three to five minutes. However, the typical
Web surfer stayed on the line for hours. This meant that the tele-
phone companies were caught with their trunks down. They simply
did not have enough ports to support the demand, causing conges-
tion at the CO and in the network.
Armed with this new set of needs and the rising demand curve,
the telephone companies sought help from the manufacturers. Ini-
tially, the carriers began espousing the death of the Public Switched
Telephone Network (PSTN) as we know it. Circuit switching is sup-
posed to be dead, and packet switching is alive and well. The argu-
ment was that if we could selectively route the voice calls into the