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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Andrea,<br><br>You have misunderstood. Legitimate spots are *<b>not</b>* being discarded.<br><br>Because:-> </span><span style='color:blue;background:white'>most of the traffic sent today is very likely fake. <-<br><br><o:p></o:p></span></p><p class=MsoNormal><span style='color:blue;background:white'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:blue;background:white'><br></span><span style='color:black;background:white'>73 de WR3D</span><span style='mso-fareast-language:EN-US'><br><br><br><o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><b><span lang=EN-US>From:</span></b><span lang=EN-US> Dxspider-support <dxspider-support-bounces@tobit.co.uk> <b>On Behalf Of </b>IZ2LSC via Dxspider-support<br><b>Sent:</b> 17 February 2025 10:09<br><b>To:</b> The DXSpider Support list <dxspider-support@tobit.co.uk><br><b>Cc:</b> IZ2LSC <iz2lsc.andrea@gmail.com><br><b>Subject:</b> Re: [Dxspider-support] Here we are again (huge flooding)<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>Kin, <o:p></o:p></p></div><div><p class=MsoNormal>how many legitimate spots is senderverify=2 discarding during normal conditions?<o:p></o:p></p></div><div><p class=MsoNormal>I understood this is still work in progress as from Dirk email he got 60% of spots dropped. This is not fine:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:blue;background:white'>"</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='color:blue;background:white'>The result I got for a morning's traffic (the natural result of a grepdbg on today's log with sendverify set) is:</span><o:p></o:p></p></div><p class=MsoNormal><span style='color:blue;background:white'><br> 60.22 (%)<br><br>Or to put it another way, most of the traffic sent today is very likely fake.<br><br><span class=gmail-il>Houston</span>, we have a problem...</span><o:p></o:p></p><div><p class=MsoNormal><span style='color:blue;background:white'>"</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Andrea<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal>--><o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Mon, Feb 17, 2025 at 8:45 AM Kin via Dxspider-support <<a href="mailto:dxspider-support@tobit.co.uk" target="_blank">dxspider-support@tobit.co.uk</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm'><p class=MsoNormal>Hi,<br><br>From the last attack I have seen the following:<br>* Link crashes with partners. With greater impact on those with less hw<br>resources.<br>* Delays of up to 5 minutes in sending spots to users in some of the larger<br>nodes.<br>* More affected on Windows than on Linux.<br>* On my node with 'set/var $DXProt::senderverify 2' the behaviour was as<br>expected, no forged spots were fake.<br> grep -i "bad spot" 047.dat | wc -l<br> 287005 <-- EA4URE-2<br> 381899 <-- EA3CV-2<br><br> 1739707974^(*) PCPROT: Bad Spot CR3DX on 14089.6 by<br>N3LPT-3(70.139.124.201)@SM4ONW-14 User N3LPT-3 not on node SM4ONW-14, DUMPED<br> 1739707974^(*) PCPROT: Bad Spot CR3DX on 7025.0 by<br>N0LPT-3(70.139.201.124)@SP6MI-2 User N0LPT-3 not on node SP6MI-2, DUMPED<br> 1739707974^(*) PCPROT: Bad Spot CR3DX on 28431.4 by<br>N3LPT-3(70.139.124.201)@PA0ESH-3 User N3LPT-3 not on node PA0ESH-3, DUMPED<br> 1739707974^(*) PCPROT: Bad Spot CR3DX on 21132.3 by<br>N5LPT-3(70.124.139.201)@GB7NHR User N5LPT-3 not on node GB7NHR, DUMPED<br> 1739707974^(*) PCPROT: Bad Spot CR3DX on 28438.0 by<br>N0LPT-3(70.201.139.124)@PI1LAP-1 User N0LPT-3 not on node PI1LAP-1, DUMPED<br><br> On my other node without enabling this feature, thousands of them were<br>received.<br>* The attack was based on varying the fields: spotted, comment, spotter,<br>spotter ip and source node.<br>* It appears that the spots were not sent from the source nodes listed in<br>the spots. I have verified that the ones where my node appears as the source<br>node, did not come from my node, so I think that this must have happened to<br>most of them.<br><br>My own conclusions<br>* Dirk's algorithm was successful for nodes that used $DXProt::senderverify<br>to remove dupes.<br>* If the attack had been without 'dupes', it could not have been stopped.<br>* The flood of spots that inundated the network clearly affected nodes with<br>fewer resources, with a less efficient OS or with a sw other than spider.<br><br>Kin EA3CV<br><br><br><br><br>_______________________________________________<br>Dxspider-support mailing list<br><a href="mailto:Dxspider-support@tobit.co.uk" target="_blank">Dxspider-support@tobit.co.uk</a><br><a href="https://mailman.tobit.co.uk/mailman/listinfo/dxspider-support" target="_blank">https://mailman.tobit.co.uk/mailman/listinfo/dxspider-support</a><o:p></o:p></p></blockquote></div></div></body></html>