Usage

This service is provided by a port 43 Whois server at bttf-whois.measurement.network.
The query format is 1.1.1.1/32 20220123 where the date is YYYYMMDD.
Bulk queries can be made using the following format:

begin
1.1.1.1/32 20220123
1.1.1.1/32 20110928
8.8.8.8/32 20220128
44.0.0.0/8 20240101
end

Output format

Responses are provided as one JSON blob per query, separated by \r\n.

{
  "IP": "45.129.95.0/24", # The network prefix from the query line
  "QDATE": "20240101", # The search date from the query line
  "results": { # null if no result found
    "prefix": "45.129.95.0/24", # The most specific prefix found matching the query
    "DATA_FIRST": "20200621", # Date the prefix was first seen in the DFZ
    "DATA_LAST": null, # Date the prefix was last seen in the DFZ, null if still in the DFZ
    "asns": [ # List of ASNs which announce this prefix
      207960
    ],
    "as2org": [ # Mappings of each announcement ASN to organisations
      {
        "ASN": 207960, # The ASN being mapped
        "ASNAME": "AS-TRANSRIGHTS", # AS Name
        "RIR": "RIPE", # Source RIR for the ASN data
        "changed": "20220101", # Last update date of the ASN data
        "opaque_id": "",
        "org": { # Organisation that owns this ASN, null if not found
          "CC": "GB", # Organisation country, ISO 3166-1 alpha 2 code
          "RIR": "RIPE", # Source RIR for the organisation data
          "ASORG": "AS207960 Cyfyngedig", # Organisation name
          "org_id": "ORG-ACP10-RIPE", # Organisation ID
          "changed": "20220101" # Last update date of the organisation data
        }
      }
    ]
  }
}

---

FAQ

What does this do?

This system lets you check who announced an IP address or prefix in the past with daily granularity, as far back as 2006.

But... why?!

So you can accurately bulk-attribute IP addresses to organizations when working with an old dataset.

This all sounds fascinating. Where can i learn more?

Here: Streibelt et al., 'Back-to-the-Future Whois: An IP Address Attribution Service for Working with Historic Datasets', Passive and Active Measurement Conference, 2023.

Do you have a privacy policy?

Yeah. Here: Logging is disabled, there are no cookies, and we only process data to provide this service (deliver this static HTML page and resolve your IP attribution requests), i.e. to provide this service (Art. 13 DS-GVO). Everything this site processes which can be traced back to you is only ephemerally held in memory and not written to disk. You can't request deletion, correction, or a copy of your data, because there is no data. The data we use to attribute IP addresses to announcing organizations are a public dataset of routing and organizational information, as publicly provided by CAIDA.