Hi Bill, > On Oct 26, 2017, at 2:37 PM, William Herrin <b...@herrin.us> wrote: > > BGP routing is based on "distance". Distance in BGP is primarily calculated > as the number of ASNs in the AS Path. Prepends make a path more distance, > encouraging routers to choose a different path if one is available.
I understand how prepends fit in the context of best path selection, but my question was more the difference between a customer signalling the ISP to prepend their AS using a BGP community stamped to a prefix vs. the customer prepending their own AS instead.
