If networks are going to make unconventional announcements, I'm not concerned if they suffer because of it.
No, no no. You're not getting it.
I'm a customer of Verizon. I'm a customer of CenturyLink. I get a /24 from CenturyLink and announce it via my two carriers: Verizon and CenturyLink. CenturyLink also announces the aggregate, let's say /16 that the /24 is a part of because all of the /16 containing my /24 is their allocation.
Get it? I announce the /24 via both so that you can reach me when there is a problem with one or the other. If you drop the /24, you break the Internet when my connection to CenturyLink is inoperable. Good job!
There is nothing unconventional about this arrangement. It was commonplace before ARIN dropped the minimum end-user assignment to /24 and many networks who themselves up that way have found it inconvenient to renumber.
Regards,
Bill Herrin
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