Ethernet in the First Mile
For engineers struggling with the IEEE standard 802.3, this book annotates and explains the dense language of the standard document, taking particular care how to explain how the EFM dovetails with other standards.
TABLE OF CONTENTS Ethernet in the First Mile
Point-to-Point Copper Objectives
The earliest Call-for-Interest presentations on Ethernet in the Last Mile (such as the one by Howard Frazier [22], later to become Chair of the EFM Task Force), identified the ELM medium as UTP POTS and the PHY as something very much like VDSL. Nevertheless, the Study Group did not approve a single copper-oriented goal at its first meeting in January 2001, partly due to the presence of a great number of people seeking to standardize fiber-based solutions, and partly because of the lack of consensus among the copper-oriented attendees. By the next meeting, the copper/fiber ratio of the audience had re-adjusted to a level where it was clear that point-to-point copper was going to be part of the EFM project, and the debate on the detailed objectives could start.
Short-Reach Objective
10PASS-TS was specified as a solution for the first concrete objective regarding operation over point-to-point copper that the EFM Task Force adopted: a PHY for a single pair of voice-grade copper, distance ? 750 m, speed ? 10 Mbps Full Duplex. [1]
The most important difference with existing twisted pair Ethernet standards is that the EFM Task Force aimed at specifying a PHY operating over a single pair, as opposed to the two pairs required for 10BASE-T, 100BASE-TX, and 100BASE-T2 or the four pairs required for 100BASE-T4, 1000BASE-T, and 10GBASE-T. [2] Although the group did review a proposal based on a lower speed, longer range version of 1000BASE-T at an early stage of its...
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