Why don't you know that? If you don't get any data for a certain time then you know there is a data loss. You can use a Trigger node for that.
If you only want data 'on demand' then just ignore the data until the time when you want it. You might, for example, use a Delay node in Rate Limit mode so that it only lets through one message per minute (or whatever you want), and ignores the rest.