So currently we have a few /24 ranges that we are looking to use on an upcoming project, we also have an ip circuit with a tier-1 ISP and bgp peering is established.

Me and my business partner know the very basics of networking and need some help. We are trying to establish the IP ranges under the ISPs ASN rather then our ASN, is there anyway we can make this happen without the ISP directly having to announce the IPs?

Example when the ip range is resolved/looked up: ASN: 1XX (ISP ASN)

rather then ASN 1XX (Our ASN)

Any help would be greatly appreciated.

Edit: Forgot to mention that the /24 ranges are added to our bgp session prefixes with the tier-1 ip circuit.

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    Commented Dec 23, 2021 at 15:49

3 Answers 3


Yes this can be done however, you will need to engage your ISP regardless as this is completely dependant on your ISPs network design and capabilities.

For example, with permission your ISP may allow you to originate this from a Private ASN over your eBGP sessions. In doing so, your ISP would then strip the Private ASN from the AS-PATH on egress to other peers.

Your ISP will more than likely need to modify route maps, prefix lists and inform neighbours of this new range.

It is also recommended that you ensure you create a ROA for the prefix with your ISPs origin AS along with RPKI signing your prefix (both of these are done with your local RIR, APNIC, AFRINIC, ARIN, RIPE etc).

It is probably important that you help us understand this design choice, is there a specific reason you do not wish to advertise this under your own ASN?

  • Hi thanks for your reply, the prefix list was updated with the ranges and an RPKI and IRR exist.
    – user73125
    Commented Jan 7, 2021 at 5:21
  • @user73125, you will still need to speak with your ISP. Most companies won't have a problem with this however they may want to nail the prefix down within their network before routing it towards you or something similar.
    – ditrapanij
    Commented Jan 7, 2021 at 5:23
  • Yes they understood the purpose of us getting a circuit with them we just don't know how to establish the private asn situation that you are explaining. The ISP already accepted the range and loa documents and added the range to the prefix list on our circuit its just a matter of establishing everything.
    – user73125
    Commented Jan 7, 2021 at 5:51
  • @user73125, usually they will tell you how they wish for this to be done. If you wanted to do it the private ASN way (and you already have a eBGP session with them from a Private ASN) all you will need to now do is redistribute the range into BGP somehow. This can be done so via a nail down route (e.g. static route for x.x.x.x/24 pointing to Null0 with a high admin distance) or by using the network x.x.x.x/24 command under your BGP instance.
    – ditrapanij
    Commented Jan 7, 2021 at 5:54

Contact your tier-1 ISP to change BGP session configuration. You need cooperation with your tier-1 ISP.

You also need to create route objects in RIR ( https://en.m.wikipedia.org/wiki/Regional_Internet_registry ) with ISP ASN and change your RPKI configuration - only if you have RPKI.

  • An RIR and RPKI already exist with the ASN needed. We are not too sure where to go from here or what we should edit in our configuration. Example of an email we received on the configuration being ready. For your BGP session ISP IP: XX.XX.XXX.XX ISP ASN: 100 (Example) Your IP: XX.XX.XXX.XX Your ASN: 105 (Example
    – user73125
    Commented Jan 7, 2021 at 5:24
  • you need to contact your ISP, best practice for this scenario is use private ASN between you and ISP.
    – lbor
    Commented Jan 7, 2021 at 5:27

If by "resolve" you mean a whois lookup (which is where traceroute gets that info), no, not if they're your address space.

If you're talking about how they appear in the global routing tables, then yes, that's a conversation to have with your ISP. To have their ASN, they have to announce them.

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