BlackEvoVii
Technical User
I understand this concept but than again i dont. Does it mean if you have a subscriber with a /20 address. The main ISP provider is advertising the address as /17 and than convinces another provider to be a back up. I understand it will advertise the /20 due to longest match. When refering to "punching a hole" does that mean that even though ISP1 is advertising the /17, the subscriber is asking ISP1 to use the more specific /20 as well? which in this case all traffic would go to the back up causing bw shortage and more complexity of managing the routing table etc...?
