jabley at ca.afilias.info
Fri Jul 21 15:38:19 UTC 2006
On 21-Jul-2006, at 11:20, Saku Ytti wrote:
> On (2006-07-21 10:48 -0400), Joe Abley wrote:
>> As it happens, Tony Li, Rex Fernando and I wrote up a proposal for a
>> new attribute which might help in some of these situations. (It's a
>> crude mechanism, but not as crude as NO_EXPORT).
> I'm sure I'm not first one to to think about 'TTL' to AS hops
> of course different reason at that time :). Other thing I was thinking
> about was ability to have include/exclude AS#'s community/attribute.
That seems to me like another perfectly valid approach, and one that
already exists to some extent (e.g. by pre-poisoning AS_PATH
attributes with AS numbers of remote networks that you don't want to
accept particular routes). I'm told that IDRP has inclusion and
exclusion lists which provide more exhaustive implementation of this
kind of idea, too.
However, for some applications those mechanisms rely on knowing the
topology one or more AS hops away from your network; AS_PATHLIMIT
doesn't. To my eye the two approaches seem complementary.
[To be clear, incidentally, Tomy, Rex and I made no claim to be the
original authors of the idea we were documenting in this draft:
The editors would like to acknowledge that they are not the original
initiators of this concept. Over the years, many similar proposals
have come our way, and we had hoped that self-discipline would cause
this type of mechanism to be unnecessary. We were overly
The names of those who originally proposed this are now lost to the
mists of time. This should rightfully be their document. We would
like to thank them for the opportunity to steward their concept to
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