CSMA discounts and campsites

[Welshbeef]

Im a member and last year at the Silverstone Classic I'd forgotten my CSMA card so just camped in the field accross the road - which was fine but no showers.

Anyway I noticed that there were signs for CSMA at silverstone but I didnt look into it?

So what is it all about? Does it have a campsite on circuit, does it have ticket discounts etc.

Any info/advice welcome