Introduction
We seem to be in one of those rare moments in our history when absence has paradoxically emerged as the strongest proof of omnipresence. Since its rather humble beginnings back in 1973, Ethernet has metamorphosed so dramatically, it bears almost no resemblance today to its origins. As testimony to its ever-increasing popularity, 95 percent of all local area networks (LANs) in existence today are estimated to be Ethernet-based. But the irony is Ethernet may likely never have been around in its current form had it not been conceived way back then in its now-extinct form.
The basic purpose of Ethernet remains unchanged—to connect computers, printers, servers, and so on in LANs so they can exchange information and services among themselves. ...

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