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[802.3_10SPE] A comment on 'Open issues on the 1000m link specification'

Slide 3 asserts that ‘In the range of 10 MHz to 20 MHz IEEE 802.3 links and ISO cabling standards specify a slope for return loss.’ and proposes changing our adopted baseline ‘To harmonize it is proposed to specify the same slope as all others between 10 and 20 MHz’.

Doing a quick check I don’t see much evidence to support this, specifically:

100BaseT1 has constant R.L. up to 20MHz:

1000BaseT1 has a slope beyond 10MHz:

1000BaseT has constant R.L. up to 20MHz:

So the proposed change seems to be harmonizing specifically with 1000BaseT1, is there some good reason to do this ?