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234 Chapter 9

Faster, Better, Cheaper

What is apparent thus far is that the movement from carriers and
manufacturers is to develop the systems that operate faster, better,
and cheaper. The older (if this is a realistic word) networks were
based on voice-centric services.Voice was and still is the primary rev-
enue producer for the carriers; therefore, they cannot ignore its
importance. If all we needed to provide were voice and low-speed
data, then we could continue to use the optical systems of the past,
providing one wavelength on each fiber and using TDM in the form
of SONET/SDH. The existing networks as we know them are shown
in Figure 9-13 with the combination of older technologies in place.
These systems still work; there should be no mistake about this.
However, as we have seen, these systems are becoming passé. The
need to manipulate the bandwidth and provide more raw power is
becoming evident, but making it happen as a quality transition is
also important. The networks of the past will not scale to the degree
we need for the future bandwidth needs of other services.
The voice communications architecture was disrupted by the
explosion of the Internet when IP protocols brought about cheaper,
faster, and better ways to handle data traffic. Shortly after the
changes brought about by the Internet, we saw the migration of
voice architecture onto packet data networks. Optical networks and
switching systems represent the same positive disruption to the
backbone networks. Carriers now will be able to handle massive
amounts of information for a lower cost per bit than ever before.
What is more interesting is that the cost of ownership and construc-
tion of these higher-speed networks is 60 percent lower than the cost
of the initial rings (SONET/SDH) installed in the 1980s and 1990s.
Moreover, the need for redundancy is lessened with wavelength
manipulation, creating a faster recovery methodology. The providers
can move away from slower protocols and unreliable transport sys-
tems. They also can move away from SONET multiplexers and cre-
ate optical switching at lower cost. The network can be minimized,
and the amount of infrastructure can be lowered. An example of this
is reflected in the number of new fiber miles that are being installed.
Figure 9-14 shows that the need for new fiber is diminishing,