I wonder whether there are clock generators with on-chip temperature sensing...
Yes: "an advanced, low-power, high-performance mobile clock generator with four clock outputs. The device integrates a MEMS resonator, temperature sensor and a temperature-to-digital converter (TDC), which eliminates the need for external crystal and temperature-sensing crystal resonators." -- https://www.sitime.com/products/clock-generators/clock-gener...
The paper mentions TCXOs and OCXOs, respectively temperature and oven-controlled crystal oscillator. You can get PCIe cards that have these on them, and devices for audio studios with a rubidium oscillator like the Tascam CG-1800.
The CG-1800 uses "a high-precision OCXO (oven-controlled crystal oscillator)" https://tascam.com/us/product/cg-1800/ only mention of rubidium is: "An external input connector that supports a 10MHz signal enables the CG-1800 to be connected to a rubidium clock or GPS clock for even higher precision."
From TFA: "Some commercial PTP implementations use packet delay variation
(PDV) filters [27], and compensate for known latencies in the receive and transmit paths."
This is phrased vaguely. All gPTP implementations are required to compensate for link delay (not necessarily rx/tx asymmetry).
I wonder whether there are clock generators with on-chip temperature sensing...
Yes: "an advanced, low-power, high-performance mobile clock generator with four clock outputs. The device integrates a MEMS resonator, temperature sensor and a temperature-to-digital converter (TDC), which eliminates the need for external crystal and temperature-sensing crystal resonators." -- https://www.sitime.com/products/clock-generators/clock-gener...
The paper mentions TCXOs and OCXOs, respectively temperature and oven-controlled crystal oscillator. You can get PCIe cards that have these on them, and devices for audio studios with a rubidium oscillator like the Tascam CG-1800.
Jane Street has a podcast that lifts the veil a little bit on how they keep their gear synced up, which is pretty interesting: https://signalsandthreads.com/clock-synchronization/
The CG-1800 uses "a high-precision OCXO (oven-controlled crystal oscillator)" https://tascam.com/us/product/cg-1800/ only mention of rubidium is: "An external input connector that supports a 10MHz signal enables the CG-1800 to be connected to a rubidium clock or GPS clock for even higher precision."
On the other hand, Antelope Audio 10MX is a rubidium word clock source: https://en.antelopeaudio.com/products/10mx/
Surplus rubidium frequency standards are cheap on Ebay: https://www.diyphysics.com/2012/02/14/d-i-y-10-mhz-atomic-cl...
From TFA: "Some commercial PTP implementations use packet delay variation (PDV) filters [27], and compensate for known latencies in the receive and transmit paths."
This is phrased vaguely. All gPTP implementations are required to compensate for link delay (not necessarily rx/tx asymmetry).