Re: [Idr] Request to adopt draft-heitz-idr-large-community

IDR Team,

I am Tom Daly from Fastly, Inc. - AS54113 - a global content delivery
networks. I'm writing to express our support of BGP Large Communities. As a
large user of IP anycast routing, we commonly use BGP communities to
control route propagation via transit providers, peers, and IXP route
servers. This draft increases our functionality to express policy.

First, as others have written, our ability to express policy towards four
byte ASNs is limited.

Second, while opaque, the construct of <ASN1>:<ASN2>:<PARAMETER> is very
logical to us an operator. Using this construct makes the application of
BGP communities - on who and via whom - very simple for a human being to
understand. Incredibly useful during situational debugging. Simplicity is
elegant in a world of more and more complex APIs.

Also worth mentioning that Fastly's implementation/adoption would be
accelerated due to our use of BIRD as a routing daemon. We understand a
patch is already underway which would allow us to rapidly test and adopt.

We are also happy to see the support of the vendor community behind this
effort: http://largebgpcommunities.net/implementations/

Thanks,
Tom

On Tue, Sep 6, 2016 at 7:39 AM, Job Snijders <job@ntt.net> wrote:

> Dear IDR, fellow network operators,
>
> I would like to request that the IDR Working Group adopts
> draft-heitz-idr-large-community [1] as a working group document.
>
> Background
> ----------
> RFC1997 BGP communities are the most common method to signal
> meta-information between autonomous systems. RFC1997 communities are a
> 32 bit entity. The convention is that the first 16 bits are the ASN in
> which the last 16 bits have a meaning. RFC1997 is so popular because of
> its elegant simplicity and ubiquitous support.
>
> The operator community (no pun intended!) is suffering from a fatal
> flaw. One in five ASNs in the Default-free zone are a 4-byte ASN (RFC
> 4893). One cannot fit a 32-bit value into a 16-bit field.
>
> 4-byte ASN Operators work around this issue by either resorting to
> kludges such as using private 16-bit ASNs as in the "Global
> Administrator" field, or by returning the ASN to their respective RIR
> and requesting a 16-bit ASN. However, both the RIRs and the IANA have
> depleted their supply of 16-bit ASNs.
>
> Work to address the issue of BGP communities has been ongoing for years.
> Notable examples are 'flexible communities' (12 years ago) and 'wide
> communities' (6 years ago). The WG so far has been unable to produce an
> internet standard which enjoys a status similar to RFC1997. Now that the
> RIRs are running out, the issue has become a matter of extreme urgency.
>
> The Large BGP Community specification gives every network operator
> (regardless of whether they have a 2-byte ASN or a 4-byte ASN) 8 bytes
> to signal meta-information in an opaque fashion. This will align with
> current, well-established practices deployed by network operators.
>
> The Large BGP Community has purposefully been specified to be narrow and
> as simple as possible to meet the operator community immediate needs,
> without dissuading from existing community extensions that are in the
> standards process pipeline.
>
> The Large Community, by design, is not extendable, because extensibility
> comes at a cost. Knowing that the amount of noise generated by an idea
> is inversely proportional to the complexity of the idea, I urge the WG
> to consider the Large Community's simplicity not a disadvantage, but a
> virtue.
>
> We ask for your support in this narrow focus to re-imagine the RFC1997
> communities in this way as it should have been done when RFC4893 was
> published.
>
> Kind regards,
>
> Job Snijders
> (co-author draft-heitz-idr-large-community)
>
> [1]: https://tools.ietf.org/html/draft-heitz-idr-large-community
>
> _______________________________________________
> Idr mailing list
> Idr@ietf.org
> https://www.ietf.org/mailman/listinfo/idr
>