How about a simple proof of work test? This one though does not ask for CPU work but asks the miner for a random old transaction. If the miner really stores the entire blockchain he will not have any problem answering to that getdata request, whereas a botnet would have to ask someone else for it, which could be detected if the response time deviates too much from what has been previously measured (compare it against getdata for the block they advertise). It&#39;s not perfect but it allows an estimate of whether it is a chainless miner.<div>

<br></div><div>Regards,</div><div>Chris</div><div>--<br>Christian Decker<br><br>
<br><br><div class="gmail_quote">On Fri, May 25, 2012 at 3:17 AM, Jeff Garzik <span dir="ltr">&lt;<a href="mailto:jgarzik@exmulti.com" target="_blank">jgarzik@exmulti.com</a>&gt;</span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">

<div class="im">On Thu, May 24, 2012 at 8:57 PM, Luke-Jr &lt;<a href="mailto:luke@dashjr.org">luke@dashjr.org</a>&gt; wrote:<br>
&gt; Block times are not accurate enough for that.<br>
<br>
</div>The times in your log are very accurate, assuming your system clock is<br>
remotely accurate.<br>
<div class="im HOEnZb"><br>
--<br>
Jeff Garzik<br>
exMULTI, Inc.<br>
<a href="mailto:jgarzik@exmulti.com">jgarzik@exmulti.com</a><br>
<br>
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