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by throw0101a 1778 days ago
> single pair Ethernet

For anyone wondering:

> In addition to the more computer-oriented two and four-pair variants, the 100BASE-T1 and 1000BASE-T1 single-pair Ethernet PHYs are intended for automotive applications[17] or as optional data channels in other interconnect applications.[18] The single pair operates at full duplex and has a maximum reach of 15 m or 49 ft (100BASE-T1, 1000BASE-T1 link segment type A) or up to 40 m or 130 ft (1000BASE-T1 link segment type B) with up to four in-line connectors. Both PHYs require a balanced twisted pair with an impedance of 100 Ω. The cable must be capable of transmitting 600 MHz for 1000BASE-T1 and 66 MHz for 100BASE-T1.

> Similar to PoE, Power over Data Lines (PoDL) can provide up to 50 W to a device.[19]

* https://en.wikipedia.org/wiki/Ethernet_over_twisted_pair#Sin...

> The IEEE 802.3bu-2016[12] amendment introduced single-pair Power over Data Lines (PoDL) for the single-pair Ethernet standards 100BASE-T1 and 1000BASE-T1 intended for automotive and industrial applications.[13] On the two-pair or four-pair standards, power is transmitted only between pairs, so that within each pair there is no voltage present other than that representing the transmitted data. With single-pair Ethernet, power is transmitted in parallel to the data. PoDL defines 10 power classes, ranging from .5 to 50 W (at PD).

* https://en.wikipedia.org/wiki/Power_over_Ethernet#PoDL

100BASE-T1 is IEEE 802.3bw-2015, 1000BASE-T1 is IEEE 802.3bp-2016. 2.5 Gb/s, 5 Gb/s, and 10 Gb/s over a single pair is 802.3ch-2020: the focus of these is in the embedded automotive space.

* https://blog.siemon.com/standards/ieee-p802-3ch-multi-gig-au...

1 comments

Addendum: The .3cz task force is working on 25/50/100 Gb/s over single twisted pair (two conductors) at lengths up to 11m (point-to-point):

* https://ieee802.org/3/cz/index.html