Hi All, I’m having issues with how the payload of a ping measurement is constructed. In a recent experiment, I found that not all probes correctly embed the probe ID into the payload. For example, the following payload is a correct example. [4, 255, 0, 1, 0, 25, 253, 117, 26, 85, 207, 174, 0, 0, 0, 0, 192, 94, 125, 241, 173, 37, 232, 44, 82, 73, 80, 69, 32, 65, 116, 108, 97, 115, 32, 112, 114, 111, 98, 101, 32, 49, 48, 50, 50, 49, 0, 0, 0, 0, 0, 0] Includes “[82, 73, 80, 69, 32, 65, 116, 108, 97, 115, 32, 112, 114, 111, 98, 101, 32]” as the ASCII of “RIPE Atlas probe ”, and “[32, 49, 48, 50, 50, 49]” as probe ID “10221” However, in a randomized sample of 50 probes, 34 of them do not have the probe ID following “RIPE Atlas probe" [82, 0, 0, 1, 113, 214, 8, 0, 0, 0, 0, 0, 129, 197, 72, 49, 0, 0, 0, 0, 0, 0, 0, 0, 171, 144, 68, 164, 87, 28, 143, 103, 0, 0, 0, 0, 82, 73, 80, 69, 32, 65, 116, 108, 97, 115, 32, 112, 114, 111, 98, 101] While considering the chance that older firmware versions do not recognize the configuration option, I disabled the ‘include_probe_id’ option. None of the payloads in this experiment includes the “RIPE Atlas probe” part. Does anyone have experience with this issue? I do notice that there are about 8 bytes shared between packets from the same probe and the same measurement, but it seems more like a randomized identifier. Thanks, Yi