Why We Use Standards and Do Compliance Testing Ethernet designs adhere to the IEEE 802.3 standard, which defines the Physical and Data Link layer of the seven-layer Open Systems Interconnection (OSI) model. Waveform characteristics are specified in the standard. Designing to this standard allows compatibility and interoperability with other devices, in all kinds of environments all over the world. Otherwise, transmission issues and data losses are likely to occur. Compliance testing ensures that the implementation meets the standard. In addition to the waveform characteristics specified in the IEEE 802.3 standard, the University of New Hampshire InterOperability Laboratory (UNH-IOL) has provided standard conformance test procedures for those signals. The documents can be found at these links: •
https://ieeexplore.ieee.org/browse/standards/get-program/page/series?id=68
•
https://www.iol.unh.edu/
Ethernet Physical Layer Basics The Ethernet standard is several thousand pages, so we’ll just cover the most important concepts and some key terminology.
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