Does Lansweeper connect to each computer in turn, or does it attempt multiple simultaneous connections?
Simultaneous, you can change the amount of simultaneous scans from the configuration.
Different behaviors would have a significantly different network impact. Another way to look at this is to report (a) the average time it takes Lansweeper to connect, download, and disconnect to each computer, and (b) the amount of data transmitted in the download (kilobytes? megabytes?). Again, if the time taken to connect/download/disconnect is minutes long, it could have a noticeable impact on the performance of the computer. So--does Lansweeper log this information (and can it log this information)? That's what we are looking for.
In the action screen you can see (at the bottom) the time it take to scan each item.
You can tweak the waittime so that not everything is scanned everytime.
Scanning should have little performance impact since it runs as a background thread.