Using counter as a way to identify unique data sample

Here is the scenario, I have more than one PC setup connected to a USB Modem that is configured with the same network ID and AES Key. These PCs are in the same building and therefore are collecting the same broadcasts from some of the deployed sensors since they are close enough. I understand that ideally a different network ID can be set, but I want these end users to be able to move these sensors around somewhat freely without having to go through a reconfiguration step. I also know repeaters could be spread out, but the number of walls and distance isn’t the best case for repeaters. I am working on figuring out a way to prevent duplicate data in this scenario as both of these PCs are sending the data to a web service that is then inserting into a single database.

My first thought is if the DB server sees a data sample within X number of seconds of the previous, then it likely is the same and just discard it. However, this may throw away valid data for some sensors that are not timer based like the proximity sensor or push button.

My next thought was using the counter in the payload within node-red. I was thinking if the counter value for this sensor already exists within the past 10 minutes (to account for a sensor reset or counter rolling over), then it is likely a duplicate and can be discarded.

TLDR: Is the the counter in the payload unique for each data sample until the counter number rolls over? Does it roll over? What is the max value for the counter? Do all sensors have counter as part of their payload so that I can depend on that value existing and use it as a sorta unique identifier for the particular node’s sample?

I am also open to any other ideas to uniquely identify the data sample. I don’t imagine there is some GUID in there for each sample that isn’t being exposed in the json payload is there?

This is the counter I am talking about. In this case it is a 3-Channel Thermocouple, but I also want to know if all sensors have this:

Yes, all sensors send the counter value.
the counter range is 0-255 and then it rolls over.

Counter value and the time difference between the last two packets can be used to discard duplicate packets.

Thanks Bhaskar, I will use that method to detect duplication then.