
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.

On Wed, Apr 05, 2000 at 05:11:02PM -0400, Daniel L. Golding wrote:
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.
Here in europe (RIPE instead of ARIN), you can request PI space, without any guaranties of it being routeable, but it usually is.
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.
Actually I've helped quite a few such customers, my recommendation usually is to get PI space from RIPE, and get both providers to announce it from their ASN, this works quite well, and also save a ASN - if the customer really want to run BGP, we have arrangements with other ISP's here, that we find a private ASN (that none of us use currently), and assign this ASN to the customer, and we then strip the private ASN on the edges of our network.
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.
Naturally there is room for everybody, but things still need to work. /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.

-----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of Jesper Skriver Sent: Friday, April 07, 2000 2:21 PM To: Daniel L. Golding Cc: David Harrison; nanog@merit.edu Subject: Re: Policies: Routing a subset of another ISP's address block
Actually I've helped quite a few such customers, my recommendation usually is to get PI space from RIPE, and get both providers to announce it from their ASN, this works quite well, and also save a ASN - if the customer really want to run BGP, we have arrangements with other ISP's here, that we find a private ASN (that none of us use currently), and assign this ASN to the customer, and we then strip the private ASN on the edges of our network.
this is interesting (since it overwrites the rule that multihoming to two isps requires a public asn assignment) and i've tested exactly this scenario (again, a customer uses some private asn and is peering with two isps; both of them strip this asn at their boundaries (remove-private-as)) in my lab before and it worked fine. it results in propagating routes to the same networks with two distinct as path attributes, though. i've been looking for any operational experience with this setup. so, do you claim that you couldn't detect *any* problems with this setup? -- dima.
participants (3)
-
Daniel L. Golding
-
Dmitri Krioukov
-
Jesper Skriver