At a routing and peering level. Once you have an announcement for your netblock out there, traffic will start to head towards it. A lot of this is due to the

At a routing and peering level. Once you have an announcement for your netblock out there, traffic will start to head towards it. A lot of this is due to the BGP Path Selection Algorithm. You can try and influence how traffic arrives, by doing things like, AS prepends, but you are still going to get traffic. The main reason for this is that the other side that is egressing to you has their own egress policy that also follows path selection. Things like localpref and weight will force my traffic to leave via a path before it considers how a network has AS padded. As an example: Lets say I want to egress (company A) to a downstream company (company B). If I learn routes to Company B via multiple ways: peering fabric (low cost), paid peering (medium cost), transit1 (high cost, variable quality), transit2 (low cost variable quality), I can choose which way my traffic goes, via localpref, weight etc. Only when I view the paths equally (equal localpref, weight etc.) will I evaluate the shortest AS Path (which the receiving company has influence on). The only way to completely not get inbound traffic via a specific link, is to remove your BGP advertisement for your netblock from that link. (some providers also let you do this selectively via BGP communities). There are also some other tips/tricks - such as adding a more specific prefix to a certain link, to attract traffic, but care needs to be made to have a fallback route in case things go wonky.