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H for high-sensitivity works for me. It would also means that it’s a receiver characteristic which may make some people more comfortable if we call it HLR4 instead.
Thanks for bringing this up via the exploder.
A difficulty with your proposal of using “H” for either “Higher power” or “Higher intensity” is that the total average launch power max for LR4 is greater than that for ER4. The OMA max power for the two is the same and only the Average min and OMA min are lower for LR4 than ER4.
I think that describing ER4 as “higher power” cannot really be defended.
Total average launch power (max) 10.5 8.9 dBm
Average launch power, each lane (max) 4.5 2.9 dBm
Average launch power, each lane (min) –4.3 -2.9 dBm
Optical Modulation Amplitude (OMA), each lane (max) 4.5 4.5 dBm
Optical Modulation Amplitude (OMA), each lane (min) –1.3 0.1 dBm
The real difference between the two PMDs is that the ER4 receiver is much more sensitive than the LR4 receiver (-21.4 dBm vs. -8.4 dBm) which enables longer reach.
The unused letters on the list in booth_01_0709.pdf are A, H, J, N, V, Y
Assuming that the Task Force were to agree to change the nomenclature, I think that you would need something like
100GBASE-HR4 – long wavelength with high sensitivity
100GBASE-VR4 – long wavelength with very long reach
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From: Brad Booth
I wanted to call to your attention that I’ve submitted a comment against the definition of SR and LR, and against the use of ER in P802.3ba.
802.3 has been very consistent over the last 10 years in trying to maintain nomenclature definitions. While people in the industry may have used S for short-reach, L for long-reach and E for extended-reach, the real use of them in IEEE Std. 802.3-2008 is for short wavelength, long wavelength and extra long wavelength.
I believe that it would be good for the Task Force to maintain consistency with the base standard so that there is no confusion when the P802.3ba amendment is merged into the base document.
I’ve attached a document that highlights how 802.3 has been using its nomenclature. The original document was created in 2000 (during 802.3ae) and has been updated and followed since that time.
The proposals in my comments are to maintain consistency for SR and LR. For ER, I am proposing a new nomenclature: HR. The “H” in my comment refers to higher-power 1310nm wavelength optics.
Upon further thought, I have realized that the term “higher-power” may carry some baggage. I also realized that there may be a desire for other optical PMDs to have greater optical power. The term “higher-intensity” may be better. And it may be more appropriate to follow what LRM did and create a 3 letter acronym: LRH or HLR (I prefer the latter).
I would be interested in hearing any feedback and thoughts you may have.