google ipv6 routes via cogent

Job Snijders job at
Sat Mar 4 02:05:15 UTC 2017

On Fri, Mar 03, 2017 at 09:42:04AM -0500, Patrick W. Gilmore wrote:
> On Mar 3, 2017, at 7:00 AM, Nick Hilliard <nick at> wrote:
> > Niels Bakker wrote:
> >> As I explained in the rest of my email that you conveniently didn't
> >> quote, it's so that you can selectively import routes from all your
> >> providers in situations where your router cannot handle a full table.
> > 
> > it can also break horribly in situations where the provider is providing
> > "transit" but doesn't provide full transit.
> > 
> > OTOH, if you are single-homed, it is highly advisable to accept a
> > default, the reason being that most transit providers provide bgp
> > communities with "don't advertise to customers" semantics.  So if you're
> > single-homed and use a full dfz feed without default route, you will not
> > have full connectivity to all the routes available from the transit
> > provider.


> If you are single-homed, there is no need for BGP at all.

That is very strongly worded, and in plenty of cases a false assertion.

> And injecting your ASN into the table is probably not terribly useful
> to everyone else’s FIB.

ASNs don't have anything to do with FIB.

> There are, of course, corner cases. But in general, single-homed
> people shouldn’t be using BGP.

There are numerous reasons to use BGP when single-homed:

    - as preparation to multi-home in the (near) future
    - ability to quickly change providers
    - to use BGP based blackholing features
    - to save time on provisioning work (adding new prefixes becomes a
      matter of just announcing and updating IRR/RPKI).
    - loadbalanacing / loadsharing across multiple links
    - ability to use bgp communities for traffic engineering

In other words, if you have your own IP space, I'd recommend to get your
own ASN and use BGP.

Kind regards,


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