Downstream Usage-BGP Communites

[nick at flhsi.com (Nick Olsen)]

Greetings NANOG,
Was hoping to gain some insight into common practice with using BGP 
Communities downstream.

For instance:
We peer with AS100 (example)
AS100 peers with TW Telecom (AS4323).
Since I happen to know that AS100 doesn't sanitize the communities I send 
with my routes. I can take advantage of TW Telecom's BGP communities for 
traffic engineering. Such as 4323:666 (Keep in TWTC Backbone). Would this 
be something that is generally frowned upon? Still under the assumption 
that the communities aren't scrubbed off my routes. Could I do this with 
other AS's beyond TW Telecom? Such as TW's peering with Global Crossing 
(AS3549)?

Nick Olsen
Network Operations (855) FLSPEED  x106