Complete Routed-Space DNS Lookups

This dataset contains PTR and SOA DNS lookups of every routed IPv4 address using a recursive resolver from hosts at CAIDA.

Complete Routed-Space DNS Lookups

We performed the lookups using one of two tools. For older datasets, we used a custom parallel DNS lookup tool based on libunbound, a component of the Unbound validating, recursive, caching DNS resolver. For newer datasets, beginning with 2018-08-23, we use zdns in iterative mode. To determine routed addresses, we use BGP tables collected by RIPE and RouteViews via BGPstream. Lookups of the full routed space take 2-3 weeks to complete.

In the 2014-08-22 dataset, we queried 2.7 billion addresses in 10.6 million /24 prefixes (for this particular dataset, we did not query the .0 and .255 addresses in each /24, but all future datasets will query these as well).

Currently available datasets are

  • 2019-01-25
  • 2018-08-23
  • 2017-09-08
  • 2015-09-17
  • 2014-08-22

File format

Result files are in a simple tab-separated, line-oriented text format.

A PTR result has the following fields:

   timestamp   IP_address      hostname

An SOA result has the following fields:

   timestamp   IP_address       name                      ns         mbox                  serial    refresh retry expire  ttl
   1537482068 201808220 86400   300   3600000 86400

Acceptable Use Agreement

Access to these data is subject to the terms of the following CAIDA Acceptable Use Agreement

When referencing this data (as required by the AUA), please use:

The CAIDA UCSD Complete Routed-Space DNS Lookups Dataset - <dates used>,
You are required to report your publications using this dataset to CAIDA.

Request Data Access

  • Request Access to the CAIDA Complete Routed-Space DNS Lookups Dataset

Topology Datasets


For more information on CAIDA topology measurements, see:

For more information on topology measurements in general see:

Related Objects

See to explore related objects to this document in the CAIDA Resource Catalog.
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