RE: Purchasing IPv4 space - due diligence homework

[Torres, Matt via NANOG]

Thanks NANOG. For those interested, here is a summary list of due diligence 
tasks for purchasing IPv4 on the secondary market:

  1.  Check out the seller (Google search). What is their story? Generally 
avoid hosting companies because they may have more block/black list cleanup to 
do.
  2.  Check the BGP looking glass Internet routing table. Make sure the IPv4 
address is not routed right now.
  3.  Check the historical Internet routing table. It is a good sign if the 
IPv4 network was advertised from the right company/ASN without recent changes 
https://stat.ripe.net/widget/routing-history#
  4.  Check ARIN registration. Singular, long standing registration for the 
IPv4 space is a good sign.
  5.  Check block list / black list. SORBS and Spamhaus are good resources. It 
is a good sign if the IPv4 network does not show up at all. 
http://www.anti-abuse.org/multi-rbl-check/
  6.  Check geo-location. It is a good sign if the IPv4 space shows up in the 
right global region. Try MaxMind.
  7.  There is a PowerShell script (that can be expanded on) to help expedite 
the checking process. 
https://www.saotn.org/powershell-blacklist-check-script/#more-2459

Thanks,
Matt

Re: Purchasing IPv4 space - due diligence homework

[Marco Davids via NANOG]

Op 04-04-19 om 01:14 schreef Mike Hammett:

Do you have sources for the ~90% T-Mobile IPv6? Not arguing, but to use 
that as a source myself when spreading the IPv6 good word.




https://www.worldipv6launch.org/apps/ipv6week/measurement/images/graphs/T-MobileUSA.png

https://stats.labs.apnic.net/ipv6/US (a bit slow, but informative)

--
Marco

Re: Purchasing IPv4 space - due diligence homework

[Mike Hammett]

Do you have sources for the ~90% T-Mobile IPv6? Not arguing, but to use that as 
a source myself when spreading the IPv6 good word. 




- 
Mike Hammett 
Intelligent Computing Solutions 
http://www.ics-il.com 

Midwest-IX 
http://www.midwest-ix.com 

- Original Message -

From: "Jared Mauch"  
To: "Matt Torres"  
Cc: nanog@nanog.org 
Sent: Wednesday, April 3, 2019 10:58:23 AM 
Subject: Re: Purchasing IPv4 space - due diligence homework 



> On Apr 3, 2019, at 11:20 AM, Torres, Matt via NANOG  wrote: 
> 
> All, 
> 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? 
> 
> My current list is: 
> • Check BGP looking glass for route. It should not show up in the Internet 
> routing table. If it does, walk away. 
> • 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. 
> • Check SORBS blacklisting. It should not show up except maybe the DUHL 
> list(?). If it does, walk away. 
> 
> Anything else? Advise? 

I’d like to ask a related question (I’m not questioning why you need IPv4 
space) but are you also deploying IPv6 as well? If not, is there a reason? In 
my copious spare time I’m doing a small FTTH network and many services do work 
well with IPv6 while others (banks are a an example) perhaps don’t. 

We have T-Mobile USA saying with their network most bits go out as v6, so I’m 
guessing there’s that 5-10% you need v4 for if you deploy as aggressively as 
they do. 

Mostly curious if you are doing IPv6 if you see that slowing your need for v4 
or if they are growing at the same rate. 

- Jared 

Re: Purchasing IPv4 space - due diligence homework

[Martin Hannigan]

Jeffrey,

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.

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.

Best,

-M<

On Wed, Apr 3, 2019 at 15:38 Jeffrey Hathaway via NANOG 
wrote:

> Hi,
>
>
>
> 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.
>
>
>
>
>
> *Sincerely,*
>
> *Jeffrey Hathaway*
>
> Information Technology • Howard Center Inc.
>
>
>
>
>
> *From:* NANOG  *On Behalf Of *Torres, Matt via
> NANOG
> *Sent:* Wednesday, April 3, 2019 11:20 AM
> *To:* nanog@nanog.org
> *Subject:* Purchasing IPv4 space - due diligence homework
>
>
>
> All,
>
> 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?
>
>
>
> My current list is:
>
>1. Check BGP looking glass for route. It should not show up in the
>Internet routing table. If it does, walk away.
>2. 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.
>3. Check SORBS blacklisting. It should not show up except maybe the
>DUHL list(?). If it does, walk away.
>
>
>
> Anything else? Advise?
>
> Thanks,
>
> Matt
>
>
> --
>
> *HowardCenter.org* 
> 
> 
> 
> 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
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> 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, da...@howardcenter.org. Thank you.
>

Re: Purchasing IPv4 space - due diligence homework

[William Herrin]

On Wed, Apr 3, 2019 at 8:20 AM Torres, Matt via NANOG 
wrote:
> due diligence research on an IPv4 block [...] what results from those
checks should cause us to walk away?

Hi Matt,

I think it also depends on your intended use. If you want a flawlessly
clean block you can use for anything, you'll spend more time and money than
if it just has to accommodate a particular use case.

Run a mail server? Better be clean as a whistle. Geolocation only
moderately important.

Eyeball source? Past mail abuse may not be an issue but past DOS source
could be and woe betide those who don't pay attention to where in the world
Maxmind thinks the block is located.

We, DNS or game servers? It almost doesn't matter. Unless past abuse was so
bad that folks straight-up black holed it in the network, users will be
able to connect to you.

It's also worth considering whether you can move non-sensitive services
from older known-clean addresses to the new blocks, freeing those older
addresses for use in the more challenging application.

Regards,
Bill Herrin

-- 
William Herrin  her...@dirtside.com  b...@herrin.us
Dirtside Systems . Web: 

RE: Purchasing IPv4 space - due diligence homework

[Jeffrey Hathaway via NANOG]

Hi,

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.


Sincerely,
Jeffrey Hathaway
Information Technology * Howard Center Inc.


From: NANOG  On Behalf Of Torres, Matt via NANOG
Sent: Wednesday, April 3, 2019 11:20 AM
To: nanog@nanog.org
Subject: Purchasing IPv4 space - due diligence homework

All,
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?

My current list is:

  1.  Check BGP looking glass for route. It should not show up in the Internet 
routing table. If it does, walk away.
  2.  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.
  3.  Check SORBS blacklisting. It should not show up except maybe the DUHL 
list(?). If it does, walk away.

Anything else? Advise?
Thanks,
Matt



HowardCenter.org 
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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 
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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, 
da...@howardcenter.org. Thank you.

Re: Purchasing IPv4 space - due diligence homework

[Nikolas Geyer]

The issue isn’t with Spamhaus itself per se, more providers who implement 
automated edge filters based on those lists and then take a long time to get 
removed manually.

Sent from my iPhone

On Apr 3, 2019, at 1:40 PM, Eric Dugas 
mailto:edu...@unknowndevice.ca>> wrote:

I cleaned two blocks last year with Spamhaus and others. Took me less than two 
weeks and Spamhaus were the quickest of the bunch (we're talking about a full 
or two business days). PSN can be tricky, same for Netflix and whatnot but I 
always put these new blocks in "quarantine" for a couple of weeks by using 
these services with random IPs in a new block.

In order, I began to announce the prefixes right after the transfers were 
approved by ARIN. I then contacted Spamhaus and the others roughly a week 
later. As I mentioned, Spamhaus were really reactive. The others responded in 
about 2 weeks.

What helped us (I think) is that we're a listed MANRS participant (so 
filtering, BCP38, proper NOC/Ops contacts). We also sign all of our routes with 
ROAs, proper route objects in an IRR and PTRs generated for every IPs.

On Apr 3 2019, at 1:20 pm, Nikolas Geyer 
mailto:n...@neko.id.au>> wrote:
A big +1 to checking Spamhaus, specifically their DROP and EDROP lists. These 
two lists are what causes us most pain when acquiring IPv4 space as a lot of 
providers put auto blocking in place based on these two which can be difficult 
to get removed.

I won’t even contemplate prefixes on either of these lists unless the seller 
knocks $5/IP off the purchase price because of the associated time and pain 
trying to clean it up.

Sent from my iPhone

On Apr 3, 2019, at 11:49 AM, Valdis Klētnieks 
mailto:valdis.kletni...@vt.edu>> wrote:

On Wed, 03 Apr 2019 15:20:17 -, "Torres, Matt via NANOG" said:

3. Check SORBS blacklisting. It should not show up except maybe the DUHL 
list(?). If it does, walk away.

SORBS isn't the only place to check. As an example, if Spamhaus doesn't have
nice things to say about the block, it's time to start asking questions

http://www.anti-abuse.org/multi-rbl-check/ has a fairly good list of
places that could give your customer a bad time (whether or not the
listing is deserved - the point is that being listed anywhere there will
probably mean problems that have to be cleaned up)

You may all now begin the religious war over where else to check.

Re: Purchasing IPv4 space - due diligence homework

[Eric Dugas]

I cleaned two blocks last year with Spamhaus and others. Took me less than two 
weeks and Spamhaus were the quickest of the bunch (we're talking about a full 
or two business days). PSN can be tricky, same for Netflix and whatnot but I 
always put these new blocks in "quarantine" for a couple of weeks by using 
these services with random IPs in a new block.

In order, I began to announce the prefixes right after the transfers were 
approved by ARIN. I then contacted Spamhaus and the others roughly a week 
later. As I mentioned, Spamhaus were really reactive. The others responded in 
about 2 weeks.
What helped us (I think) is that we're a listed MANRS participant (so 
filtering, BCP38, proper NOC/Ops contacts). We also sign all of our routes with 
ROAs, proper route objects in an IRR and PTRs generated for every IPs.
On Apr 3 2019, at 1:20 pm, Nikolas Geyer  wrote:
> A big +1 to checking Spamhaus, specifically their DROP and EDROP lists. These 
> two lists are what causes us most pain when acquiring IPv4 space as a lot of 
> providers put auto blocking in place based on these two which can be 
> difficult to get removed.
>
> I won’t even contemplate prefixes on either of these lists unless the seller 
> knocks $5/IP off the purchase price because of the associated time and pain 
> trying to clean it up.
> Sent from my iPhone
> > On Apr 3, 2019, at 11:49 AM, Valdis Klētnieks  
> > wrote:
> > On Wed, 03 Apr 2019 15:20:17 -, "Torres, Matt via NANOG" said:
> > > 3. Check SORBS blacklisting. It should not show up except maybe the DUHL 
> > > list(?). If it does, walk away.
> > SORBS isn't the only place to check. As an example, if Spamhaus doesn't have
> > nice things to say about the block, it's time to start asking questions
> >
> > http://www.anti-abuse.org/multi-rbl-check/ has a fairly good list of
> > places that could give your customer a bad time (whether or not the
> > listing is deserved - the point is that being listed anywhere there will
> > probably mean problems that have to be cleaned up)
> >
> > You may all now begin the religious war over where else to check.

Re: Purchasing IPv4 space - due diligence homework

[Nikolas Geyer]

A big +1 to checking Spamhaus, specifically their DROP and EDROP lists. These 
two lists are what causes us most pain when acquiring IPv4 space as a lot of 
providers put auto blocking in place based on these two which can be difficult 
to get removed. 

I won’t even contemplate prefixes on either of these lists unless the seller 
knocks $5/IP off the purchase price because of the associated time and pain 
trying to clean it up. 

Sent from my iPhone

> On Apr 3, 2019, at 11:49 AM, Valdis Klētnieks  wrote:
> 
> On Wed, 03 Apr 2019 15:20:17 -, "Torres, Matt via NANOG" said:
> 
>>  3.  Check SORBS blacklisting. It should not show up except maybe the DUHL 
>> list(?). If it does, walk away.
> 
> SORBS isn't the only place to check. As an example, if Spamhaus doesn't have
> nice things to say about the block, it's time to start asking questions
> 
> http://www.anti-abuse.org/multi-rbl-check/ has a fairly good list of
> places that could give your customer a bad time (whether or not the
> listing is deserved - the point is that being listed anywhere there will
> probably mean problems that have to be cleaned up)
> 
> You may all now begin the religious war over where else to check.
> 
> 

Re: Purchasing IPv4 space - due diligence homework

[Jared Mauch]

> On Apr 3, 2019, at 12:04 PM, Valdis Klētnieks  wrote:
> 
> On Wed, 03 Apr 2019 11:58:23 -0400, Jared Mauch said:
> 
>> Mostly curious if you are doing IPv6 if you see that slowing your need for v4
>> or if they are growing at the same rate.
> 
> And remember kids - the more you can push off to native IPv6, the longer you 
> can
> push off an upgrade to your CGNAT box. ;)

For me, this is a big reason why if you’re doing CGNAT you want to compliment 
it with IPv6.  

At IETF last week there was an interesting discussion about the fact that 
things like DHCPv6-PD does not explicitly say that a DHCPv6-PD prefix should be 
inserted into the routing table (!), and you may not have the tools you need to 
mange these prefixes as a result.  In DHCPv4 land of course you give out 
prefixes that are connected, but in DHCPv6-PD you may get something from a /56 
to a /64 which may mean that route needs to go into your IGP.

- Jared

Re: Purchasing IPv4 space - due diligence homework

[Valdis Klētnieks]

On Wed, 03 Apr 2019 11:58:23 -0400, Jared Mauch said:

> Mostly curious if you are doing IPv6 if you see that slowing your need for v4
> or if they are growing at the same rate.

And remember kids - the more you can push off to native IPv6, the longer you can
push off an upgrade to your CGNAT box. ;)

Re: Purchasing IPv4 space - due diligence homework

[Jared Mauch]

> On Apr 3, 2019, at 11:20 AM, Torres, Matt via NANOG  wrote:
> 
> All,
> 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?
>  
> My current list is:
>   • Check BGP looking glass for route. It should not show up in the 
> Internet routing table. If it does, walk away.
>   • 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.
>   • Check SORBS blacklisting. It should not show up except maybe the DUHL 
> list(?). If it does, walk away.
>  
> Anything else? Advise?

I’d like to ask a related question (I’m not questioning why you need IPv4 
space) but are you also deploying IPv6 as well?  If not, is there a reason?  In 
my copious spare time I’m doing a small FTTH network and many services do work 
well with IPv6 while others (banks are a an example) perhaps don’t.

We have T-Mobile USA saying with their network most bits go out as v6, so I’m 
guessing there’s that 5-10% you need v4 for if you deploy as aggressively as 
they do.

Mostly curious if you are doing IPv6 if you see that slowing your need for v4 
or if they are growing at the same rate.

- Jared

RE: Purchasing IPv4 space - due diligence homework

[Sam Roche]

I used this gentleman’s Powershell script and modified it slightly to check a 
block last summer. The broker we were using said that they also did their due 
diligence on the addresses, but I wanted to do our own because of the cost of 
the IPs.

https://www.saotn.org/powershell-blacklist-check-script/

We worked with the Brander Group as a broker. They were great and have since 
launched a portal/storefront I believe.

Kind regards,

Sam.

From: NANOG  On Behalf Of John Alcock
Sent: Wednesday, April 3, 2019 11:34 AM
To: Torres, Matt 
Cc: nanog@nanog.org
Subject: Re: Purchasing IPv4 space - due diligence homework

Well,

I did all three above and still had issues.  I am still having issues.  I had 
to contact many people to get off of various blacklists, etc.  These are lists 
that are not publish and you will not know until you start using the space.

Luckily, I have had great help from the list here in getting support and in 
some cases back-channel support.

The hard part is getting a hold of the right people.

For example:

Softlayer/IBM was initially blocking my ip space.  But, it was not really them. 
 It was NTT on behalf of Softlayer.  The request has to come from Softlayer.  
That has been resolved.  I honestly do not even know who to thank.

I am currently fighting the same issue with 
playstation.com<http://playstation.com>.  Akami is blocking access on behalf of 
Sony.  The request has to come from Sony.  After many emails with 
abuse@playstation, I am making headway.  Problem is not solved yet, but I 
believe they are making headway. Luckly Akami open a ticket and told me what to 
tell the Sony NOC.


Right now, I am fighting some odd ball blocks.  Several mobile banking sites.  
There is not even a support number.  I am having to try and use the NOC/Abuse 
contacts via ARIN first and not having any luck.  Try calling a bank and 
telling them that your are a network engineer and can not access their sites.  
That goes downhill pretty quick. If you can get past the first line of tech 
support it is a challenge.  "Have you cleared your cookies?  You need to call 
your ISP", then you get a 2nd line person who basically blows you off.

Here is the thing.  You will have problems.  Just be prepared to make lots of 
phone calls and send lots of emails.  Once you get to the right person, things 
can get a moving.

John


On Wed, Apr 3, 2019 at 11:20 AM Torres, Matt via NANOG 
mailto:nanog@nanog.org>> wrote:
All,
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?

My current list is:

  1.  Check BGP looking glass for route. It should not show up in the Internet 
routing table. If it does, walk away.
  2.  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.
  3.  Check SORBS blacklisting. It should not show up except maybe the DUHL 
list(?). If it does, walk away.

Anything else? Advise?
Thanks,
Matt

Re: Purchasing IPv4 space - due diligence homework

[Valdis Klētnieks]

On Wed, 03 Apr 2019 15:20:17 -, "Torres, Matt via NANOG" said:

>   3.  Check SORBS blacklisting. It should not show up except maybe the DUHL 
> list(?). If it does, walk away.

SORBS isn't the only place to check. As an example, if Spamhaus doesn't have
nice things to say about the block, it's time to start asking questions

http://www.anti-abuse.org/multi-rbl-check/ has a fairly good list of
places that could give your customer a bad time (whether or not the
listing is deserved - the point is that being listed anywhere there will
probably mean problems that have to be cleaned up)

You may all now begin the religious war over where else to check.

Re: Purchasing IPv4 space - due diligence homework

[Matt Harris]

On Wed, Apr 3, 2019 at 10:34 AM John Alcock  wrote:

> Well,
>
> I did all three above and still had issues.  I am still having issues.  I
> had to contact many people to get off of various blacklists, etc.  These
> are lists that are not publish and you will not know until you start using
> the space.
>
> Here is the thing.  You will have problems.  Just be prepared to make lots
> of phone calls and send lots of emails.  Once you get to the right person,
> things can get a moving.
>
> John
>

My experience has been quite different and quite a bit better.  One of the
things I paid attention to was whom the previous owner of the block was,
what sort of company they were, and hence what their likely use case was.
I have purchased/deployed a few /23s so far and have yet to run into any
issues with blacklists.  Some of the space I've purchased came from a
small-town ISP which was acquired, and some came from newly-defunct
retail-sector organizations.  I stayed away from anything that had been
associated with any sort of hosting, or that seemed to have been leased out
in the past, etc.  You can often check historical routing tables to see if
more than one AS has announced the space in the past X number of years to
identify blocks that have been leased around, and that's one other
component you might want to consider looking at.  But ultimately I think my
best tactic has been to just check out the organization I'm acquiring it
from and make sure they've owned it since the beginning via ARIN records.
Dealing with a reputable broker is probably a good start, too.  I've had no
issues working with Hilco.

Good luck!

Re: Purchasing IPv4 space - due diligence homework

[John Alcock]

Well,

I did all three above and still had issues.  I am still having issues.  I
had to contact many people to get off of various blacklists, etc.  These
are lists that are not publish and you will not know until you start using
the space.

Luckily, I have had great help from the list here in getting support and in
some cases back-channel support.

The hard part is getting a hold of the right people.

For example:

Softlayer/IBM was initially blocking my ip space.  But, it was not really
them.  It was NTT on behalf of Softlayer.  The request has to come from
Softlayer.  That has been resolved.  I honestly do not even know who to
thank.

I am currently fighting the same issue with playstation.com.  Akami is
blocking access on behalf of Sony.  The request has to come from Sony.
After many emails with abuse@playstation, I am making headway.  Problem is
not solved yet, but I believe they are making headway. Luckly Akami open a
ticket and told me what to tell the Sony NOC.


Right now, I am fighting some odd ball blocks.  Several mobile banking
sites.  There is not even a support number.  I am having to try and use the
NOC/Abuse contacts via ARIN first and not having any luck.  Try calling a
bank and telling them that your are a network engineer and can not access
their sites.  That goes downhill pretty quick. If you can get past the
first line of tech support it is a challenge.  "Have you cleared your
cookies?  You need to call your ISP", then you get a 2nd line person who
basically blows you off.

Here is the thing.  You will have problems.  Just be prepared to make lots
of phone calls and send lots of emails.  Once you get to the right person,
things can get a moving.

John


On Wed, Apr 3, 2019 at 11:20 AM Torres, Matt via NANOG 
wrote:

> All,
>
> 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?
>
>
>
> My current list is:
>
>1. Check BGP looking glass for route. It should not show up in the
>Internet routing table. If it does, walk away.
>2. 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.
>3. Check SORBS blacklisting. It should not show up except maybe the
>DUHL list(?). If it does, walk away.
>
>
>
> Anything else? Advise?
>
> Thanks,
>
> Matt
>
>
>