Ethernet Technology Consortium Releases Specifications for 800Gbit/s Ethernet

The Ethernet Technology Consortium has released the specifications of the 800Gbit/s Ethernet standard. It is based on the IEEE 802.3 standard for 400Gbit/s Ethernet.

The Ethernet Technology Consortium reports that the 800 GbE standard uses 400 Gbit/s logic as much as possible. The 800Gbit/s specification introduces a new media access control and an updated physical coding sublayer, both of which are based on current 400Gbit/s technologies. A new physical medium dependent sublayer for 800Gbit/s is not yet defined in the specification. Two 400Gbit/s PMDs could be used to form an 800Gbit/s interface, but that requires the skew to be managed to fit the specification, the consortium writes.

The 800Gbit/s specification is based on the IEEE 802.3bs standard for 400Gbit/s Ethernet, which was rolled out in 2018. That standard uses multi-lane distribution to distribute the data from a single MAC across sixteen PC lanes. The 800Gbit/s standard, in turn, uses an 800Gbit/s MAC and two modified 400Gbit/s PCs to drive eight lanes of 106.25Gbit/s each. So in total there are 32 PC lanes, which have RS(544,514) forward error correction.

The IEEE 802.3 standard also uses unique alignment markers for each virtual lane. Such markers are entered every 163,840x257b blocks. This remains the same for 800Gbit/s, but the amount of markers is doubled and adapted to the needs of the 800Gbit/s standard.

The group behind the Ethernet standard was previously known as the 25 Gigabit Ethernet Consortium, but this name was changed along with the release of the 800 GbE specification. The consortium was set up to develop standards for 25Gbit/s, 50Gbit/s and 100Gbit/s Ethernet. The old name therefore no longer made sense, the consortium reported.

A block diagram of the 800Gbit/s MAC