At the the IEEE-SA December 2017 Standards Board Meeting, IEEE Std 802.3bs™-2017, which specifies 200 Gigabit and 400 Gigabit Ethernet operation, was ratified. In moving Ethernet past 100 Gigabits per second, a whole new family of optical physical layer specifications (PHY) for 200GbE and 400GbE were defined, see Table 1 and Table 2. To enable these new rates of Ethernet, a new architecture was defined that included the inclusion of an “extender” sublayer to provide future proofing.

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