Re: Networks ignoring prepends?

[Tom Beecher <beecher () beecher cc>]

> I feel your pain Bill, but from a slightly different angle.  For years the
> large CDNs have been disregarding prepends.  When a source AS disregards
> BGP best path selection rules, it sets off a chain reaction of silliness
> not attributable to the transit AS's.  At the terminus of that chain are
> destination / eyeball AS's now compelled to do undesirable things out of
> necessity such as:
>   1) Advertise specifics towards select peers - i.e. inconsistent edge
> routing policy & littering global table
>   2) Continuing to prepending a ridiculous amount anyway
> Gotta wonder how things would be if everyone just abided by the rules.

What 'rule' are you asserting is being broken here?



On Mon, Jan 22, 2024 at 9:56 PM Jeff Behrns via NANOG <nanog () nanog org>
wrote:

> > > William Herrin <bill () herrin us> wrote:
> Until they tamper with it using localpref, BGP's default behavior with
> prepends does exactly the right thing, at least in my situation.
>
> I feel your pain Bill, but from a slightly different angle.  For years the
> large CDNs have been disregarding prepends.  When a source AS disregards
> BGP best path selection rules, it sets off a chain reaction of silliness
> not attributable to the transit AS's.  At the terminus of that chain are
> destination / eyeball AS's now compelled to do undesirable things out of
> necessity such as:
>   1) Advertise specifics towards select peers - i.e. inconsistent edge
> routing policy & littering global table
>   2) Continuing to prepending a ridiculous amount anyway
> Gotta wonder how things would be if everyone just abided by the rules.