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Center for Applied Internet Data Analysis > data : passive : telescope-near-real-time_dataset.xml
Historical and Near-Real-Time UCSD Network Telescope Traffic Dataset
This dataset consists of hourly files of raw IPv4 packets of unsolicited traffic captured by the UCSD Network Telescope instrumentation.

Data Description

The UCSD Network Telescope consists of a globally routed, but lightly utilized /8 network prefix, that is, 1/256th of the whole IPv4 address space. It contains few legitimate hosts; inbound traffic to non-existent machines - so called Internet Background Radiation (IBR) - is unsolicited and results from a wide range of events, including misconfiguration (e.g. mistyping an IP address), scanning of address space by attackers or malware looking for vulnerable targets, backscatter from randomly spoofed denial-of-service attacks, and the automated spread of malware. CAIDA continously captures this anomalous traffic discarding the legitimate traffic packets destined to the few reachable IP addresses in this prefix. We archive and aggregate these data, and provide this valuable resource to network security researchers.

This dataset represents raw traffic traces captured by the Telescope instrumentation and made available in near-real time as one-hour long compressed pcap files. We collect more than 3 TB of uncompressed IBR traffic traces data per day. The most recent 60 days of data are stored locally at CAIDA. Once data slides out of ths "near-real-time window", the pcap files are off-loaded to a tape storage. This historical Telescope data starting from 2008 are available by additional request.

Caveats that apply to this dataset

This dataset and the types of worm and denial-of-service attack traffic contained therein are representative only of some spoofed source denial-of-service attacks. Many denial-of-service attackers do not spoof source IP addresses when they attack their victim, in which case backscatter would not appear on a telescope. Attackers can also spoof in a non-random fashion, which will incur an uneven distribution of backscatter across the IPv4 address space, and may cause backscatter traffic to miss any telescope lenses. Note that the telescope does not send any packets in response, which also limits insight into the traffic it sees.

Data Access Policy

These data must be analyized on CAIDA machines, and cannot be downloaded!

Academic researchers, government agencies and corporate entries in the DHS-Approved Locations can only request access through Information Marketplace for Policy and Analysis of Cyber-risk and Trust (IMPACT) portal. In order for the application to be considered, the researchers must obtain an IMPACT account as well as complete and agree to IMPACT Memorandum of Agreement (MOA).

Academic researchers from other foreign countries can request access through CAIDA by filling out and submitting the online form. It usually takes about five to ten business days to process your request. We carefully review each application and the decision to grant the data access is based on the merits of your proposed data use.

Finally, these data also may be available for government and corporate entities not from DHS-Approved Locations who participate in CAIDA's membership program. Information on membership levels, services, and rates can be found on the CAIDA Sponsorship Information page, or by emailing

Once users are approved for access to this dataset, they will be set up with an account on the CAIDA machine that provides direct access to the Telescope data they requested. Accounts will be valid for a nominal twelve months in which the research is expected to be completed. CAIDA strictly enforces a "take software to the data" policy for this dataset: all analysis must be performed on CAIDA computers; no download of raw data will be allowed. CAIDA provides several basic tools to access the dataset, including CoralReef and Corsaro. Researchers can also upload their own analysis software.

Acceptable Use Agreement

Access to these data is subject to the terms of the following CAIDA Acceptable Use Agreement (printable version in PDF format)
and the supplemental AUA below:

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

The CAIDA UCSD Network Telescope Traffic Dataset - < dates used >,
Also, please, report your publication to CAIDA.

UCSD Network Telescope Datasets


For more information about the use of these data in studies of internet censorship, see:

For more information on Conficker and worm attacks, see:

For more information on Backscatter and Denial-of-Service attacks, see:

For more information on the UCSD Network Telescope, see:

For more information on the CoralReef Software Suite, see:

For more information on the Corsaro Software Suite, see:

For a non-exhaustive list of Non-CAIDA publications using Network Telescope data, see:

  Last Modified: Wed Mar-27-2019 22:23:18 PDT
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