Looking for information on Insight reputation lookups

Can anyone point me to some documentation on the insight reputation lookups that go out to https://ent-shasta-rrs.symantec.com

I am trying to determine how much bandwidth my clients will use if I open this up, and how often they will go out to get new reputation data.

If I have 10,000 clients and push out a software update to all clients, will all clients in turn querry that URL for insight updates to check on the new files they just received?  Or will one go out, see it is a known good file, and all subsequent clients will not need to query https://ent-shasta-rrs.symantec.com for updates?

Thanks.