On Fri, Aug 27, 2010 at 04:57:17PM -0400, Valdis.Kletnieks@vt.edu wrote:
On Fri, 27 Aug 2010 13:43:39 PDT, Clay Fiske said:
If -everyone- dropped the session on a bad attribute, it likely wouldn't make it far enough into the wild to cause these problems in the first place.
That works fine for malformed attributes. It blows chunks for legally formed but unknown attributes - how would you ever deploy a new attribute?
This is covered by the RFC. Unknown attributes are either dropped or passed on depending on the attribute flags. The problem as in AS4 was that there where illegally formed unknown attributes that got passed around and made RFC compliant routers, which already handled AS4, further down the chain fail. This problem was addressed in "Error Handling for Optional Transitive BGP Attributes" but for some reasons people think it is necessary to make something simple more and more complex so this draft is still pending. -- :wq Claudio