The PHY (Physical Layer Device) operates at the physical layer (Layer 1) of the OSI model and is responsible for: The PHY converts digital signals from the MAC into analog electrical or optical signals for transmission over copper (e., CAT6 cables via RJ45) or fiber (e., SFP. While these two concepts are indeed related, Ethernet is simply an interface specification (IEEE 802. 3) comprising many subsections and specifications defining the physical and data-link layers of the Open Systems Interconnection (OSI) model. Here's a. An optical module is a typically hot-pluggable optical transceiver used in high-bandwidth data communications applications. Optical modules typically have an electrical interface on the side that connects to the inside of the system and an optical interface on the side that connects to the outside. I see that it has an RJ-45 port with a physical PHY and a port for an SFP module that would require an FPGA-based PHY IP core.
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