<div><div><br></div><div dir="auto">Jeffrey,</div><div dir="auto"><br></div><div dir="auto">Thanks. A good start, but under-scoped. When you are purchasing IP number blocks whatever source you use; a marketplace, a broker, a single source should provide you with a compelling history on a number block REPUTATION that includes all the attributes listed below and then some. Some of the blocks I’ve seen being discussed lately appear notorious. In one case I counted 17 difffernt RBL’s being attributed to it. Checking Spamhaus is good, but then there are many others and some not so well known. There are many embedded in devices (remember auto config) that will never be updated. </div><div dir="auto"><br></div></div><div dir="auto">For most, do not buy v4 numbers blocks without a pro and you’ll sorta know when they talk about everything but price. Price matters, but if its unusable or you need to spend a month cleaning it up, no income = more cost. </div><div dir="auto"><br></div><div dir="auto">Best, </div><div dir="auto"><br></div><div dir="auto">-M<</div><div><div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, Apr 3, 2019 at 15:38 Jeffrey Hathaway via NANOG <<a href="mailto:nanog@nanog.org" target="_blank">nanog@nanog.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div lang="EN-US" link="#0563C1" vlink="#954F72">
<div class="m_3798617156031205932m_-3908363328496647379WordSection1">
<p class="MsoNormal"><span style="color:#1f497d">Hi,<u></u><u></u></span></p>
<p class="MsoNormal"><span style="color:#1f497d"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="color:#1f497d">While I think #3 is important, it depends on your use of the end-block, and those entries can sometimes be cleaned up with some work. If the block is listed, that would certainly lower my buying price I am willing
to pay for the block. I did buy a block once in the ARIN region which showed up in IP geolocation databases as Russian (no idea why), but it took me quite a while to get it fixed.
<u></u><u></u></span></p>
<p class="MsoNormal"><span style="color:#1f497d"><u></u> <u></u></span></p>
<div>
<p class="MsoNormal"><b><span style="font-family:"Garamond",serif;color:#003b49"><u></u> <u></u></span></b></p>
<p class="MsoNormal"><b><span style="font-family:"Garamond",serif;color:#003b49">Sincerely,<u></u><u></u></span></b></p>
<p class="MsoNormal"><b><span style="font-family:"Garamond",serif;color:#003b49">Jeffrey Hathaway</span></b><span style="font-family:"Garamond",serif;color:#003b49"><u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-family:"Garamond",serif;color:#003b49">Information Technology • Howard Center Inc.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="color:#1f497d"><u></u> <u></u></span></p>
</div></div></div><div lang="EN-US" link="#0563C1" vlink="#954F72"><div class="m_3798617156031205932m_-3908363328496647379WordSection1">
<p class="MsoNormal"><span style="color:#1f497d"><u></u> <u></u></span></p>
<div>
<div style="border:none;border-top:solid #e1e1e1 1.0pt;padding:3.0pt 0in 0in 0in">
<p class="MsoNormal"><b>From:</b> NANOG <<a href="mailto:nanog-bounces@nanog.org" target="_blank">nanog-bounces@nanog.org</a>> <b>On Behalf Of
</b>Torres, Matt via NANOG<br>
<b>Sent:</b> Wednesday, April 3, 2019 11:20 AM<br>
<b>To:</b> <a href="mailto:nanog@nanog.org" target="_blank">nanog@nanog.org</a><br>
<b>Subject:</b> Purchasing IPv4 space - due diligence homework<u></u><u></u></p>
</div>
</div>
<p class="MsoNormal"><u></u> <u></u></p>
<p class="MsoNormal">All,<u></u><u></u></p>
<p class="MsoNormal">Side stepping a migration to IPv6 debate…. I’d like to hear advise from the group about performing due diligence research on an IPv4 block before purchasing it on the secondary market (on behalf of an end-user company). My research has
branched into two questions: a) What ‘checks’ should I perform?, and b) what results from those checks should cause us to walk away?<u></u><u></u></p>
<p class="MsoNormal"><u></u> <u></u></p>
<p class="MsoNormal">My current list is:<u></u><u></u></p>
<ol style="margin-top:0in" start="1" type="1">
<li class="MsoNormal">Check BGP looking glass for route. It should not show up in the Internet routing table. If it does, walk away.<u></u><u></u></li><li class="MsoNormal">Check the ARIN registry. The longer history without recent transfers or changes is better. I don’t know what explicit results should cause me to walk away here.<u></u><u></u></li><li class="MsoNormal">Check SORBS blacklisting. It should not show up except maybe the DUHL list(?). If it does, walk away.<u></u><u></u></li></ol>
<p class="MsoNormal"><u></u> <u></u></p>
<p class="MsoNormal">Anything else? Advise?<u></u><u></u></p>
<p class="MsoNormal">Thanks,<u></u><u></u></p>
<p class="MsoNormal">Matt<u></u><u></u></p>
<p class="MsoNormal"><u></u> <u></u></p>
</div></div><div lang="EN-US" link="#0563C1" vlink="#954F72"><div class="m_3798617156031205932m_-3908363328496647379WordSection1"></div>
<hr style="border:0;border-top:solid 1px #005957;height:1px;line-height:1px;margin:10px 0">
<p><a href="http://howardcenter.org" style="font-size:12px;text-decoration:none" target="_blank"><font face="Arial" color=" #005957"><strong>HowardCenter.org</strong></font></a>
<a href="http://www.facebook.com/pages/HowardCenter/106516727431" target="_blank"><img style="border:none" src="http://howardcenter.org/assets/design/Facebook.jpg" align="absmiddle"></a><a>
</a><a href="https://twitter.com/HowardCenterVT" target="_blank"><img style="border:none" src="http://howardcenter.org/assets/design/Twitter.jpg" align="absmiddle"></a><a>
</a><a href="http://www.linkedin.com/company/HowardCenter" target="_blank"><img style="border:none" src="http://howardcenter.org/assets/design/LinkedIn.jpg" align="absmiddle"></a><a>
</a></p>
<font face="Arial" color="#666666" size="1">CONFIDENTIALITY NOTICE: This e-mail is intended only for the use of the individual or entity to which it is addressed and may contain information that is patient protected health information, privileged, confidential
and exempt from disclosure under applicable law. If you have received this communication in error, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. Please notify the sender by reply e-mail
and delete the original message immediately, or notify Howard Center, Inc. immediately by forwarded e-mail to our Privacy Officer, <a href="mailto:DaveK@howardcenter.org" target="_blank">DaveK@howardcenter.org</a>. Thank you.</font>
</div>
</blockquote></div></div>
</div>