proxies - invisible?

[Unregistered]

I've used proxies for some time and find them great to minimize spam, etc. but the question remains, can one be traced if they use a proxy? I'm familiar with ISP logs but in general if an end-site wants to know who looked at such and such, can they track it back to a specific machine? And does multiple (stacked) proxies make it harder? Just curious, no secret agent fantasies here :) Thanks for the help!

[mbravo]

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Yes, from properly logged (at the proxy) connection it is possible to trace the origination point. Of course, multiple hops and all the other "covering your tracks" tricks work, but so do the forensic teams - it's always a race.

Secret agent realities, exactly :)

I recommend that you read a book by Cliff Stoll - The Cuckoo's Egg - while it's not about http proxies, but it is about this race, very well-written, and as relevant today as ever. It's a classic. I've linked it for your convenience.