Re: Policies: Routing a subset of another ISP's address block

["Daniel L. Golding" <dan () netrail net>]

Jesper,

Do you then suggest the elimination of the ARIN multihomed issuance
policy - which is, BTW, the method most folks use to get PI space these
days? After all, you can't be truly multihomed without PI space in your
scheme of things. This would seriously raise the bar for folks to get PI
space in the first place.  You would effectively ban anyone doing BGP
advertisements that doesn't have their own PI space already. This is a
troublesome suggestion. It denies the benefits of multihoming to small
enterprises and ISPs, effectively discriminating against them. 

I find your line of reasoning, which is essentially "tough cookies" to be
unconvincing. I must also assume that you haven't worked for a small ISP
or CLEC recently, nor have you had such for a customer. There must be room
for providers of all sizes in the marketplace. If this thesis enjoyed
widespread acceptance by the major Tier I ISPs, I have no doubt that it
would be considered anti-competative.

- Dan Golding

On Wed, 5 Apr 2000, Jesper Skriver wrote:

> On Wed, Apr 05, 2000 at 10:45:07AM -0400, Daniel L. Golding wrote:
> > On Wed, 5 Apr 2000, Jesper Skriver wrote:
> >
> > > On Wed, Apr 05, 2000 at 08:33:25AM -0400, David Harrison wrote:
> > > > We have a situation where we have a client who wants to be dual-homed
> > > > for redundancy. They are not large enough to get addresses from ARIN.
> > > > Given that they are wanting us to allow another provider to route a
> > > > subset of one of our address blocks(5 /24's out of a /16).
> > > > Looking for some recommendation/dangers and general policies in
> > > > reference to this. Thanks for any input. If this is the incorrect list
> > > > to post this on please let me know.
> > >
> > > Refuse to do it, the customer must get PI addresses for this purpose.
> >
> > That's simply not true. Many ISPs will advertise another's netblocks for a
> > mutual downstream. The client doesn't have enough IP space to qualify for
> > PI space in any case unless they utilize a /21 to 80% while being
> > multihomed. 
>
> Bad luck ...
>
> I can say for sure, that we doesn't accept more specific announcements within 
> our PA blocks, nor does we accept traffic with a source within these
> blocks.
>
> > I don't see the logic behind refusing the customer a request of this sort.
>
> Exploding routing tables, and it makes it impossible to do anti-spoofing
> filters ...
>
> /Jesper
>
> -- 
> Jesper Skriver, jesper(at)skriver(dot)dk  -  CCIE #5456
> Work:    Network manager @ AS3292 (Tele Danmark DataNetworks)
> Private: Geek            @ AS2109 (A much smaller network ;-)
>
> One Unix to rule them all, One Resolver to find them,
> One IP to bring them all and in the zone to bind them.