Unallocated prefix in the DFZ via Cogent

Calling Cogent, Avantel (AS 6503) and Axtel (AS 14000):

Axtel is announcing, which is within the block,
which is unallocated according to


I am seeing this from two of my transit providers, the common AS path is:

  174 6503 6503 6503 6503 6503 14000

Prefix filtering is a good thing, please do it!

Steinar Haug, Nethelp consulting, sthaug@nethelp.no

I'd love to see what that prefix is doing.. :slight_smile:

Anyone have anything they can share?


As long as someone's trying to bang a few clues into Axtel, they might suggest to them that they clean up their announcements and look into aggregating the /23s in 201.158.192/18 and maybe even announcing the covering CIDR if they refuse to get rid of the deaggregation.

What all good advertised, unallocated prefixes do... send mail...
(senderbase shows a fair amount of volume)