For most of Ethernet’s history, new standards progressively added more bandwidth, expanding the top end of speed. That progression is now changing, as the IEEE has now ratified the 802.3bz standard that defines 2.5 Gbps and 5 Gbps Ethernet speeds.
In 2014, multiple groups started efforts to create new mid-tier Ethernet speeds with the NBASE-T Alliance starting in October 2014 and MGBASE-T Alliance getting started a few months later in December 2014. While those groups started out on different paths, the final 802.3bz standard represents a unified protocol that is interoperable across multiple vendors.
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