Just trying to get some clarity and direction regarding obtaining
address space/ASN for my client.
Is there a minimum address space (?) an entity would need to justify to
go directly to RIR (ARIN in this case) as opposed to the upstream
provider? Is /20 the minimum allocation? Can my client approach RIR and
request for a /23?
If my client do procure a /23 how do they make make sure that this
address space will be globally routable?
Multihome will also be part of their network implementation, can they
apply for an ASN number?
Yes, minimum assignment is /20 (and this is considered temporary, as the official minimum is /19) -- there used to be some experimental /24s, but I believe these are now gone. ARIN will only assign /20 or more -- larger prefixes must come from your upstream provider. Being multihomed means you will be required to get an AS number. Once you have your address block, you can fill out the request from ARIN.
> Is there a minimum address space (?) an entity would need to justify to
> go directly to RIR (ARIN in this case) as opposed to the upstream
> provider? Is /20 the minimum allocation? Can my client approach RIR and
> request for a /23?
> If my client do procure a /23 how do they make make sure that this
> address space will be globally routable?
They can't really make *sure* of it, any more than with any other
prefix.... I think there is language to that effect somewhere. That
said, I think ARIN does try to allocate these smaller allocations from a
block that is less likely to be filtered (by most networks).
Yes, minimum assignment is /20 (and this is considered temporary, as the
official minimum is /19) -- there used to be some experimental /24s,
but I believe these are now gone. ARIN will only assign /20 or more --
larger prefixes must come from your upstream provider.
Could be wrong, but my understanding is that they will allocate a /22 or
shorter when the requesting org is multihomed.
Just trying to get some clarity and direction regarding obtaining
address space/ASN for my client.
Is there a minimum address space (?) an entity would need to justify to
go directly to RIR (ARIN in this case) as opposed to the upstream
provider? Is /20 the minimum allocation? Can my client approach RIR and
request for a /23?
If you ask for a /23, at this point, ARIN will most likely tell them to get additional space from their upstream. If the organization is utilizing at least a /23's worth of space now and ready to multihome, they can request a /22 from ARIN. Their IPv4 allocation policies are documented here:
If my client do procure a /23 how do they make make sure that this
address space will be globally routable?
I would recommend they register a maintainer, AS and appropriate route objects in the RADB or one of the many IRR mirrors. Some carriers build their filters based off of IRR data. That's still not a guarantee of global routability, but keeping their records in good order is a good start.
Multihome will also be part of their network implementation, can they
apply for an ASN number?
They can apply if they're close to being ready (within 30 days) to multihome.
You (your client) needs to be able to announce at least one /24 to two or more upstream providers in order to meet ARIN's criteria for assignment of an ASN. ARIN's ASN criteria are documented here:
I'll second the route registry suggestion. We turned up BGP about a year ago, and found that most of our traffic got bit-bucketed by big edge networks without registering routes. If you don't want to pay RADB, you can use AltDB.