2012/5/31 David Barak <thegameiam@yahoo.com>
From: Nick Hilliard <nick@foobar.org>
If you don't rewrite your transit providers' origin, then you are telling them that they can directly influence your exit discrimination policy on the basis of a purely advisory flag which has no real meaning.
On what precisely do you base the idea that a mandatory transitive attribute of a BGP prefix is a "purely advisory flag which has no real meaning"? I encourage you to reconsider that opinion - it's actually a useful attribute, much the way that MED is a useful attribute. Many providers re-write MED, and apparently some re-write ORIGIN. Neither of those is "network abuse" - it's more accurately described as "network routing policy." As has been stated here before: your network, your rules.
The internet by definition is a network of network so no one entity can keep traffic segregated to their network. Modifying someone else routing advertisements without their consent is just as bad as filtering them in my opinion. Doing so to move traffic into your AS in order to gain an advantage in peering arrangements and make more money off of the end user is just dastardly. The "your network your rules" philosophy doesn't work for something as large as the internet, or POTS or power grids or RF or anything else that requires multiple companies to work together. This is why we have debates on DPI and network neutrality and such. What if some country wants to block youtube and they start advertising bogus routes for it? What if our upstreams could shorten our AS paths to 1 or even shorten prefixes to drive traffic through one AS or another? Giving all control to the network operators would result in chaos.