On Fri, Oct 29, 2010 at 9:55 AM, Rettke, Brian <Brian.Rettke@cableone.biz> wrote:

My company is building a national backbone network, leveraging leased lines and dark fiber from Tier 1/2/3 providers. What we've found is that when we buy IP in the major markets, our traffic does not flow deterministically with AS-Path as the metric. This is because most of the major providers give their customers one local preference value, and their peers another, in an effort to ensure SLAs are met by keeping customer traffic on-net for as long as possible. There are varying values assigned, and some vendors don't offer community values to neutralize this effect.

I think you mean "provider" rather than "vendor"; by and large, all hardware vendors provide some knob to allow for changing localpreference values across the full range of allowable values. Providers, on the other hand, only allow customers to request a change of local preference values, and then only among a very small set of values, usually ranging from "above normal customer localpref", "default customer localpref", and "below customer localpref". If you're really lucky, they might allow you to set "peer localpref" and "below peer localpref".

I'm wondering if anyone has dealt with this in the past, or if it would be possible to have some sort of agreement on local preference manipulation. Something similar to the below:

1. All vendors must offer at least 5 community values for local preference. This is to allow for customer-based multivendor traffic engineering. 2. All vendors must offer a local preference community value greater than their best default metric. 3. All vendors must offer a local preference community value lesser than their worst default metric. 4. All vendors should offer a range of community values both above and below local preference 100.

Not everybody uses 100 as their default value, so that requirement could be at odds with the rest of the requirements. I'd recommend dropping that from your list, to make the barrier to adoption lower.

5. All vendors should make an effort to standardize the values/value ranges offered with other vendors. 6. All vendors should offer a local preference matrix to their customers, listing the changes made to a specific AS (e.g. another vendor) to aid the customer in making an intelligent routing decision for load balancing and traffic engineering in a multivendor BGP environment.

It's obviously something that each of us would need to do individually, but I'm wondering if there is any way this could become a de facto standard, or could be a method that the community at large could enforce somehow.

I'm not sure what incentive there would be for the providers to coordinate like this; it would mean quite a bit more work for them, with no appreciable gain in revenue for it. Matt

Sincerely,

Brian A . Rettke RHCT, CCDP, CCNP, CCIP Network Engineer, CableONE Internet Services

On Fri, 29 Oct 2010 09:55:06 PDT, "Rettke, Brian" said:

It's obviously something that each of us would need to do individually, but I'm wondering if there is any way this could become a de facto standard, or could be a method that the community at large could enforce somehow.

Alice's Restaurant. If one customer asks for it, if two ask for it, if 50 ask for it... Just put your requirements into the RFP, and make it clear your $$ are going to the outfit that does the best on your list of 6 requirements. Remind the losers of this. Get 49 of your friends to put it in RFP's too. The providers are *not* going to do something like this unless there's a good economic basis for doing it.