Purchased IPv4 Woes

Baldur Norddahl baldur.norddahl at gmail.com
Sun Mar 12 23:20:03 UTC 2017

Den 12/03/2017 kl. 19.24 skrev Rob McEwen:
> On 3/12/2017 2:00 PM, Baldur Norddahl wrote:
>> Den 12/03/2017 kl. 18.49 skrev Rob McEwen:
>>> This motivation goes a LONG way towards countering the profit motives
>>> that hosters/ISPs/Datacenters/ESPs have in selling services to
>>> spammers - there is MUCH money to be made doing so. But the longer
>>> term repercussions of damaged IP reputation makes that a *bad*
>>> long-term investment (even if the short-term gains are lucrative).
>> 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).
> First, I'm on the front lines of this particular fight - and my 
> conversations I have with mail senders (of all various types) gives me 
> constant 1st-hand confirmation of these facts you deny.
> But don't take my word for it - consider the following article written 
> by Brian Krebs:

How much IP address space have you bought or sold in the last year? Me? 
About 5k IP addresses, which might not be a lot but still more than most.

The article says nothing about the pricing of selling or buying IP 
address space.

Yes it is a fact that tainted address space is slightly cheaper than 
"pristine" address space. Slightly. And we will happily buy it because 
we are not using it for sending emails anyway. And so will a lot of 
other eyeball ISPs and that keeps the price up.

I am not complaining about the space we got. Some of it is tainted. We 
just assign users that complain about that some address space from 
untainted space. Most users never notice. But I can see the pain on a 
smaller hosting provider just starting out and he got unlucky with his 
first buy.

Having a spammer abuse your address space is very expensive, but NOT 
because the address space can not be sold. It can. But if you have to do 
that, you will have to tell all your other customers to change addresses 
and they will not be happy campers about that. Plus it is a lot of 
bother and I will bet you that spammers are generally not good paying 

The assertion that refusing to unblock address space that got sold 
somehow influences spammers is wrong.



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