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Is there a common source for description (like for "data link layer" and might include electrical specification of "physical layer") of 10GBASE-T as standard for technical devices?

Considering multi data rate support (10Gbps, 1Gbps, 100Mbps), modulation type BASE, compatible medium types, coding scheme 4B/5B, 8B/10B or 64B/66B, number of lanes and lane signal rates provided.

(Example, but without description for compatibility definitions for network devices: https://www.synopsys.com/designware-ip/technical-bulletin/ethernet-dwtb-q117.html#Ethernet%20Nomenclature
802.3an is a 2006-06 standard for 10GBase-T, but not publicly available? https://en.wikipedia.org/wiki/IEEE_802.3)

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10GBASE-T isn't downward comaptible (nor is any other Ethernet standard by itself). Twisted-pair Ethernet uses Autonegotiation where each side announces its capabilities (speed & duplex), so the link partners can agree on the best common protocol between them before PHY initialization begins.

The process is detailed in IEEE 802.3 Clause 28. The protocol priority is selected from the list in Annex 28B, higher is better:

a) 40GBASE-T full duplex
b) 25GBASE-T full duplex
c) 10GBASE-T full duplex
d) 5GBASE-T full duplex
e) 2.5GBASE-T full duplex
f) 1000BASE-T full duplex
g) 1000BASE-T
h) 100BASE-T2 full duplex
i) 100BASE-TX full duplex
j) 100BASE-T2
k) 100BASE-T4
l) 100BASE-TX
m) 10BASE-T full duplex
n) 10BASE-T
  • Thx Partly different experience, maybe? One device (SPT-PTTG-RS1) known to me (theoretically) seems to provide different functionality, that is not understandable, without "coding translation" between 64b66b and 8b10b and therefore "(auto)negotiation" compatible between 10GBase-T and 1000Base-T sopto.com.cn/upload/201907/25/201907251646537757.pdf ? – beyondtime Oct 13 at 18:46
  • The PCS coding is different for each speed - there's no translation however, the device uses the right one for each PHY. The transceiver you've linked to does use use trancoding though to convert between 64b66b on the SFP+ slot and 10GBASE-T. – Zac67 Oct 13 at 19:01

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