Purchased IPv4 Woes

Rob McEwen rob at invaluement.com
Sun Mar 12 18:40:24 UTC 2017

On 3/12/2017 2:00 PM, Baldur Norddahl wrote:
> Sorry but this is not true. The address space does not lose that much in
> value and in fact most address space that has been used for end users is
> already tainted in the same way (due to botnets etc).

Also, you're comparing apples-to-oranges. Dynamically allocated IPs for 
"end users" are not suppose to host mail and web servers - at least not 
professional and high-quality hosting services. This is why their 
outbound speed is almost always governed down to a trickle (often order 
of magnitudes slower then the download speeds), and port 25 is often 
blocked (when not headed to the mail server hosted by the particular ISP 
which controls that space).

Such IPs are OFTEN preemptively blacklisted by Spamhaus's PBL list:


If someone wants to run a mail server (or even a web server) from such 
space - then they have a whole bunch of OTHER problems besides who/what 
damaged the space before they acquired it. Their first problem is that 
they are trying to tow a boat with their bicycle.

Rob McEwen

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