Shared Transition Space VS. BGP Next Hop [was: Re: Best practices IPv4/IPv6 BGP (dual stack)]

joel jaeggli joelja at
Sat May 3 18:48:14 UTC 2014

On 5/3/14, 10:36 AM, Chris Grundemann wrote:
> On Sat, May 3, 2014 at 3:58 AM, Randy Bush <randy at> wrote:
>> a good number of us use that kinky /10 behind home nats and encourage
>> everyone to do so.  it was a sick deal and should be treated as such,
>> just more 1918.
> A good number of folks use other folks IP space in all kinds of
> strange and kinky ways too - it's ALL just more 1918, right??? Or
> maybe standards exist for a reason. Perhaps enhancing coordination,
> cooperation, and *interoperability* are good things... I'll let you
> decide, Randy; is it sick to solve problems through community
> consensus and standardization, or is it sick to be the one
> intentionally getting in the way of those real world solutions?

Any time you have two parties that have to interconnect who have
overlapping usage of the same space you're going to have issues.

The authors the 6598 were concerned about intersection with legacy CPE. does not  yet have that issue.  The use cases being
described here (randy causing pollution,  numbering internal network
resources (the intended purpose after all)) have no relationship to
legacy CPE.

characterizing it as shared was always a misnomer since by their nature
collisions are not sharing.

in a somewhat unrelated note this prefix is still leaking in some
globally visible ways in some places.

e.g. if you're as3303 you probably shouldn't be importing these prefixes
from customers or exporting  as part of your full table given that you
also accept them from subsidiaries. that's likely to end in tears.

> Cheers,
> ~Chris
>> randy

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 308 bytes
Desc: OpenPGP digital signature
URL: <>

More information about the NANOG mailing list