IPv4 Mismanagement

Fri Oct 2 18:50:11 UTC 2020

A service I disconnected more than 2 years ago still has a /24 of their
space SWIPED to me. Their NOC closed the ticket I opened to remove. Unknown
if it's actually in use for another customer.

I also had a conversation last week with another ISP (we were renegotiating
our contract) about this. The order form they sent me had multiple /28's we
had "given back" years ago still listed. Turns out they're still being
routed to us as well.

I would bet it happens all over the place.

-Matt

On Fri, Oct 2, 2020 at 2:00 PM Matt Hoppes <
mattlists at rivervalleyinternet.net> wrote:

> I'm sitting here in the office on a Friday performing some IP
> maintenance and I see that one of our upstreams is still filtering an IP
> range we haven't used in years.   I dig into it a bit more and it turns
> out a major carrier still has them SWIPed to us.
>
> This got me curious and I dug more into IPs from back in our early days
> and discovered there are two Tier-1 carriers we no longer do business
> with that still have large blocks of their own IPs SWIPED and allocated
> to us.
>
> This is really confusing and concerning.   I know it's not the
> end-all-be-all, but I wonder how much IPv4 exhaustion is being caused by
> this type of IPv4 mis-management, where IPs are still shown as
> "allocated" to a customer who hasn't used them in years.
>
> I've seen this behavior from Frontier and CenturyLink to name just a few.
>
> Any thoughts on this?
>
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