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PCH - DNS Query Metadata
Packet Clearing House
Packet Clearing House
Data collection is ongoing
44 (lowest rank is 56)

Category & Restrictions

DNS Data

1. Researcher shall include the following attribution statement in any publication regarding research using this dataset: "Data used in this research was collected by Packet Clearing House ( a/). Financial support for the collection of this data was provided by, among others, The U.S. Department of Homeland Security (NBCHC-0401710), and the Soros Foundation Open Society Institute (#10130), ("

2. Researcher shall forward a copy of any resulting publication, including bibliographic information, in electronic form to, or in paper form to:

Attn: Citations

Packet Clearing House

572 B Ruger Street, Box 29920

The Presidio of San Francisco

San Francisco, CA    94129-0920



Statistics on DNS query types over time.

This is DNS metadata, not an unprocessed dataset. It consists of statistics regarding the quantity and relative frequencies of different types of DNS queries over time, as observed at major authoritative and recursive domain name servers.
This dataset is the subject of ongoing measurement and data collection. As such the data is continuously growing. Researchers who are granted access will be able to download updates for a period of one year after their request.

Additional Details

Size is growing as more data is collected
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