Backward/Forward Compatibility This became a very important attribute of
Ethernet, enabling customers to use new features without having to uproot their
29 IEEE was given the Ethernet patents by Xerox and now officially licenses it to any manufacturer.
Ethernet: From LAN to the WAN 19
base infrastructure. The fundamental Ethernet frame largely remained the same30
independent of, say Ethernet??™s speed.31 This fact made it enormously easy to work with
a mish-mash of Ethernet devices and applications and led to Ethernet being perceived
as a future-proof investment that would not be obsolete in a short period.
The continual innovation and commercialization of Ethernet led to dramatic
improvements in its performance that, along with the economies of scale, meant cost
was correspondingly reduced while new demand was stimulated. Figure 1.7 generally
reflects32 the bandwidth/speed changes in Ethernet interfaces over time, with the
corresponding price per bit. The bandwidth of Ethernet cards increased tenfold
periodically for about 1/3rd increase in cost (or less with time). This led to a dramatic
decrease (about 70 percent) in the cost per bit from a customer standpoint.
Pages:
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126