[inet-ops] Prefix Pollution

[Ralph Doncaster]

On Tue, 14 Dec 2004, Michael.Dillon at radianz.com wrote:

> However, I think that the problem of pollution arises
> from people's behavior and there are some social
> engineering actions that can help.

Many customers are not aware of Arin's /22 policy, and for those that are
aware, there's often no incentive to apply for their own block.

For example I had a customer that was reassigned a /23 and /24 from my
/19.  They were multi-homed, and were also reassigned IPs from another
transit provider.  We charge a modest amount for reassignments ($35/mth
per /24) but the other provider (like most) doesn't.

After the /22 policy came out I told the customer they should get their
own /22.  They didn't.  Eventually I told them I was taking back the IPs
and gave them 2 months to renumber.  The whole process took so much work I
can see why most networks would rather just do nothing.  Updating RR
objects isn't too bad since it is automated, but upstream filter updates
generally are not.  In many cases it takes more than just an email to an
upstream to get filter changes done.

I susupect the big networks don't even know which customers would qualify
for direct assignment, so nothing will happen in this case.

One simple thing I think that would help is if transit providers set their
filters to allow for aggregation.  Let's say I'm announcing 67.8.64.0/22.
My upstreams will add this to their filters
 ... permit 67.8.64.0/22
Why not add this instead?
 ... permit 67.8.64.0/18 le 22

Overall though, I think it's a rather steep uphill battle...

-Ralph