when was it standardized?
In February 1980
Ethernet
In February 1980, the Institute of Electrical and Electronics Engineers (IEEE) started project 802 to standardize local area networks (LAN).
where does the pfe reside on an mx960 router UNANSWERABLE what is juniper mx-series? It is a family of ethernet routers and switches what is the meaning of the initial word? Ethernet is a family of computer networking technologies commonly used in local area networks (LAN),  and wide area networks (WAN)
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Ethernet [SEP] Standardization
In February 1980, the Institute of Electrical and Electronics Engineers (IEEE) started project 802 to standardize local area networks (LAN). The "DIX-group" with Gary Robinson (DEC), Phil Arst (Intel), and Bob Printis (Xerox) submitted the so-called "Blue Book" CSMA/CD specification as a candidate for the LAN specification. In addition to CSMA/CD, Token Ring (supported by IBM) and Token Bus (selected and henceforward supported by General Motors) were also considered as candidates for a LAN standard. Competing proposals and broad interest in the initiative led to strong disagreement over which technology to standardize. In December 1980, the group was split into three subgroups, and standardization proceeded separately for each proposal.