I am working with an Multi-Gigabit Ethernet Plus Switch (MS108EUP) , currently testing with embedded hardware that makes use of the 802.3bt standard. The LLDP negotiation happens as expected and power/link are both transmitted accordingly. However, when the device tries to make use of the Power via MDI Measurements, the MS108EUP does not respond.
To what extent is 802.3bt supported? Is the Measurements TLV expected to be supported?
If not, when will it be addressed?
Seemingly, the measurements capability was introduced over 4 years ago...
Not representing Netgear, however I vaguely remember when these LLDP extensions clauses were worked through on the IEEE bodies about 10 years ago, some additional Bits (Functions) were defined representing which measurements (voltage, current, energy) are available, and where/how exactly these are measured (e.g. on which pairs).
This is where I would suggest to start, instead of blindly requesting some optional data probably not available
Talking of PD or PSE measurements here?
Either way, these bits should exist in the extended table. If these don't, this would be a major omission on the MS108EUP (and probably the MS108TUP, too).
Please keep in mind, we talk of a Plus switch here, not a [smart] managed switch at all. Thus, I'll request a moderator moving this thread to the Plus and Smart Switches Forum to discuss this further on.
The bits you are referring to are directly part of the LLDP - Power via MDI Measurements TLV that I was describing.
The 802.3bt standard introduces the Measurements TLV in the 2nd amendment (IEEE 802.3bt-2018: Physical Layer and Management Parameters for Power over Ethernet over 4 pairs).
Regardless, I am trying to get at the PSE measurements.
I am running into the issue where the MS108EUP does not reply to my LLDP request if the Measurement TLV is within the packet. This happens both with all bits set to 0, as well as defining the measure source as "port total" and setting the bits for each of the corresponding voltage/current/power/energy request fields.
Made sure to update to the latest firmware release to ensure I hadn't missed any changes, but alas still can't negotiate along with measurements...
Apologies for choosing the wrong thread topic, thanks for taking the steps to get it moved to the correct place.
The 802.3bt standard introduces the Measurements TLV in the 2nd amendment (IEEE 802.3bt-2018: Physical Layer and Management Parameters for Power over Ethernet over 4 pairs).
Yes, this is what was discussed and explained in the LLDP IEEE workgroup a loong time go already.This is what I had in mind from the IEEE LLDP work from about decade ago, too.
The switch can indicate which measurements are supported, if any at all. That's why I was picky if (and how) these bits are set.
I am running into the issue where the MS108EUP does not reply to my LLDP request if the Measurement TLV is within the packet. This happens both with all bits set to 0, as well as defining the measure source as "port total" and setting the bits for each of the corresponding voltage/current/power/energy request fields.
Made sure to update to the latest firmware release to ensure I hadn't missed any changes, but alas still can't negotiate along with measurements...
Keep in mind, the “Power via MDI” TLV, is an optional TLV, “Power via MDI measurements” is also defined.
With this TLV the PSE and PD can exchange information about electrical conditions at their respective PI. Four different measurements are supported: voltage, current, power, and energy.
The devices independently can indicate which measurements are supported, which measurement they request from the link partner, what the quality of the measurement is (expressed in an uncertainty figure), and finally the measurement results itself.
This is what I had in mind from the IEEE LLDP work from about decade ago, too.
The switch can indicate which measurements are supported, if any at all. That's why I was picky if (and how) these bits are set.
