Hi Jason, The following reply which I sent to the IDR mailing list might also be helpful for you to understand the way most of these designs currently work - as well as some of the problems we encounter with the existing RFC1997 communities: http://www.ietf.org/mail-archive/web/idr/current/msg16219.html draft-heitz-idr-large-community should tackle the missing 32-bit ASN feature, but should also resolve the private AS overlapping problem you're describing in [2] since it's a 32:32:32 format rather than 16:16. Best regards, Martijn Schmidt On 09/19/2016 10:28 PM, Theodore Baschak wrote:
In a previous $dayjob at a different ASN I was customers of a large-ish regional Canadian carrier (at 100M), and also of a small local guy (at 8M) with only Cogent upstream. I would prepend out the local guy 3x, and then I also tagged 174:3003 to have cogent prepend 3x more. This worked somewhat OK to make up for the inbalance in speeds.
This type of use case is supported by, and works well with draft-heitz-idr-large-community. As an operator of a 32-bit ASN I have no ability to use communities with my ASN in them like 16-bit ASN operator could, and I have expressed so on the IETF IDR list.
Theodore Baschak - AS395089 - Hextet Systems https://ciscodude.net/ - https://hextet.systems/ http://mbix.ca/
On Mon, Sep 19, 2016 at 11:00 AM, Jason Lixfeld <jason+nanog@lixfeld.ca> wrote:
Hi,
Consider the following scenario:
- Customer A is a customer of SP A - SP A is a customer of SP B - SP B has a traffic engineering community implementation
With regards to using BGP communities for TE:
- Does SP A write their own community implementation that maps to (some portion of) the community implementation of SP B? - Does SP A write their own community implementation that has no mappings at all to the community implementation of SP B; any TE that is required to be pushed to SP B is done by some dialog and coordination between Customer A and SP A? - Does SP A allow Customer A to announce prefixes tagged with SP B’s communities[1][2] - Is this sort of thing really complicated today, but one of the goals of draft-heitz-idr-large-community?
[1] Customer A has knowledge of SP A’s upstream SP B [2] This opens up a can of worms where SP A or SP B implements some communities prefixed with reserved ASes, so we’ll assume that SP A implements some method of allowing communities prefixed with ASes of SP A and SP B only.
Thanks!