skitter

skitter is a tool for actively probing the Internet in order to analyze topology and performance.

On Feb 8, 2008, after 10 years of data collection and 4TB of data, we deactivated skitter data collection and transitioned to our next generation topology measurement infrastructure named Archipelago (Ark). We already perform large-scale topology measurements on Ark, and we recommend researchers use this new dataset, which employs an improved measurement methodology. The new IPv4 Routed /24 Topology Dataset collected on Ark extends back to Sep 13, 2007 and overlaps with the last five months of skitter data.

| Macroscopic Topology Project Skitter AS Links Dataset Request Data Access |

| skitter goals architecture ITDK results sample analysis code visualizations router adjacencies |

skitter Goals

Sample Visualization from skitter Data

The research goals of this project are described on our Macroscopic Topology Measurements page. Specific data collection goals include:

Measure Forward IP Paths
skitter records each hop from a source to many destinations. by incrementing the "time to live" (TTL) of each IP packet header and recording replies from each router (or hop) leading to the destination host.
Measure Round Trip Time
skitter collects round trip time (RTT) along with path (hop) data. skitter uses ICMP echo requests as probes to a list of IP destinations.
Track Persistent Routing Changes
skitter data can provide indications of low-frequency persistent routing changes. Correlations between RTT and time of day may reveal a change in either forward or reverse path routing.
Visualize Network Connectivity
By probing the paths to many destination IP addresses spread throughout the IPv4 address space, skitter data can be used to visualize the directed graph from a source to much of the Internet.

Research and Publications Based on Skitter Data

CAIDA publications based on skitter data
Non-CAIDA publications based on skitter data (list compiled based on Internet search)
Non-CAIDA publications using skitter data (list compiled based on feedback from skitter data users)
Non-CAIDA publications referencing skitter tool or data
Skitter data application procedure and official CAIDA Topology Data Request form for academic researchers and corporate entities (including corporate researchers) who participate in CAIDA's membership program who wish to download/use skitter data

Acceptable Use Agreement

Please read the terms of the CAIDA Acceptable Use Agreement below: (printable version in PDF format)
CAIDA ACCEPTABLE USE AGREEMENT The following terms comprise the Acceptable Use Policy (AUP) and Data License Agreement (collectively, the "AGREEMENT" or, "Acceptable Use Agreement (AUA)") for all requested CAIDA datasets. Certain datasets may have additional Supplemental provisions. References to this AGREEMENT shall include any and all relevant Supplemental provisions. CAIDA has the authority and reserves the right, in its sole discretion, to refuse requests for dataset(s) or discontinue further access and use to anyone. If You feel Your request is inappropriately denied please contact CAIDA by sending a message to data-info@caida.org. This AGREEMENT is legally binding under the laws of the State of California, United States. By requesting access to CAIDA dataset(s), You acknowledge that you understand and agree to be bound by the terms and conditions of this AGREEMENT. Any violation of this AGREEMENT may result in the immediate suspension or termination of data access and/or other action entitled by law such as injunctive or equitable relief. You are individually liable and responsible for compliance with this AGREEMENT. 1 LICENSE CAIDA's authorization to access the data grants You a limited, nonexclusive, nontransferable, terminable license to copy, modify, and use the data in accordance with this AGREEMENT solely for non-profit educational and/or research purposes. If you desire to use or otherwise incorporate any copyrightable part of this data for commercial purposes, including internal business purposes, You should contact the UC San Diego Technology Transfer Office, (858) 534-5815, fax: (858) 534-7345. 2 GENERAL CONDITIONS (i) You will not impersonate any individual or entity, misrepresent any affiliation with another person, entity or association, use false information, or otherwise conceal Your identity from CAIDA at any time for any purpose. (ii) You consent that CAIDA can make public or otherwise disclose Your name as the registrant Researcher, the name of Your Affiliated Institution, the name of the dataset(s) that CAIDA has made available to You under this AUA, and the brief description of the type of research being undertaken that You provided to CAIDA. (iii) You will abide by any and all modifications. If a modification(s) occurs, it is effective when adopted by CAIDA, and will be explicitly communicated to You via Your registered email address. Your continued access of the data indicates Your assent to any and all modification(s). If You do not agree to comply with the modification(s), You acknowledge that You will: (a) inform CAIDA immediately, at which point Your access to the data will be terminated and no longer authorized; (b) no longer access or use this data. 3 USE RESTRICTIONS If you have any concerns or questions about these restrictions, you are encouraged to contact CAIDA management via email to data-info@caida.org. To obtain an exemption from any of these restrictions, You will need a written authorization from CAIDA management. (i) You will not attempt to connect to, probe, or in any way initiate contact with a device or device administrator identified or identifiable, via IP address or otherwise, within the dataset(s). (ii) While using non-anonymized data set(s), You will respect the privacy of end users and organizations that may be identified in the data. For any publication or other disclosure, You will anonymize or de-identify IP addresses, network names, and domain names or other data identified in Supplemental provisions (if any) by using commonly accepted techniques such as one of the methods recommended by CAIDA (http://www.caida.org/projects/predict/anonymization/). (iii) While using anonymized data set(s), You will not attempt to reverse engineer, decrypt, de-anonymize, derive or otherwise re-identify anonymized information. (iv) You will not distribute, disclose, transfer or otherwise make available the dataset(s) to any person other than those employed by your institute who are assisting or collaborating with You in research using the dataset(s). Other entities with whom You are collaborating in research using the dataset(s) must request access to the dataset(s) separately and directly from CAIDA. (v) All conditions, restrictions and obligations attached to this data shall accompany any and all subsequent uses and disclosures of this dataset by You. Therefore, You are personally and fully responsible for communicating this AUA and ensuring its compliance as to any and all users described above to whom You make the data available. 4 USE OBLIGATIONS (i) If You create a publication (including web pages, papers published by a third party, and publicly available presentations) using data from this dataset, You must provide CAIDA with a copy of (or a link to) the publication and You must cite the data as follows: The CAIDA UCSD [DataSet Name] - [dates used], http://www.caida.org/data/[dataset-URL] (ii) At the end of the research, or semi-annually (whichever is sooner), You will report a summary of the research and any findings/conclusions to CAIDA. This information is used in reports to our funding agencies. 5 ACCOUNTABILITY AND ENFORCEMENT (i) You will use appropriate and reasonable care (no less rigorous than what You use to safeguard Your own similar information) in safeguarding all sensitive information in the dataset to protect the confidentiality of data and/or the privacy of any identifiable individual person, group, or organization, and to prevent its unauthorized use and disclosure. Data is not confidential, and therefore not sensitive if: (a) You already knew the data before it was disclosed to You by CAIDA; (b) You gain subsequent knowledge of the data by either lawfully obtaining it from another source under no obligation of confidentiality, or You develop it independently; (c) the data is or becomes generally available to the public through no wrongful act of You or any other party; (e) it is required to be disclosed under applicable law, regulation or court order provided You notify CAIDA prior to making such a disclosure so that CAIDA may take appropriate action. (ii) You will notify CAIDA immediately of all relevant details if: (a) confidentiality or privacy is compromised; or (b) you receive any legal, investigatory, or other government demand to reverse engineer, decrypt, de-anonymize or otherwise disclose anonymized or confidential data. (iii) If requested, You will provide CAIDA evidence of compliance with this AGREEMENT, such as a written description of Your data protection plan or a written affirmation that you have disposed of any and all copies of the received dataset from all systems reasonably known to you. (iv) DISCLAIMER OF WARRANTIES. CAIDA USES ITS BEST EFFORTS TO PROVIDE DATA IN ACCORDANCE WITH ETHICAL PRINCIPLES AND SCIENTIFIC INTEGRITY. HOWEVER, THE DATA PROVIDED HEREIN IS ON AN "AS IS" BASIS. NEITHER CAIDA, ITS RESEARCHERS, RESEARCH PARTNERS, LICENSORS, AND DATA PROVIDERS, NOR THE UNIVERSITY OF CALIFORNIA AND ITS TRUSTEES, OFFICERS, EMPLOYEES, AND AGENTS MAKE ANY WARRANTY, EITHER IMPLIED OR EXPRESS, OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, INCLUDING, BUT NOT LIMITED TO, THE ACCURACY, TIMELINESS, COMPLETENESS, RELIABILITY, OR AVAILABILITY OF CAIDA DATA, APPLICATIONS, OR SERVICES ACCESSIBLE THROUGH OR MADE AVAILABLE BY CAIDA. TO THE EXTENT ALLOWED BY LAW, YOU WILL INDEMNIFY, DEFEND AND HOLD HARMLESS CAIDA AND THE UNIVERSITY OF CALIFORNIA FROMALL LIABILITIES, CLAIMS, DEMANDS, COSTS, JUDGMENTS, DAMAGES, LOSSES AND EXPENSES ARISING OUT OF OR IN CONNECTION WITH ANY USE OF THE DATA BY YOU. IN NO EVENT SHALL CAIDA AND THE UNIVERSITY OF CALIFORNIA BE LIABLE TO YOU OR ANY THIRD PARTY FOR ANY INDIRECT, CONSEQUENTIAL, INCIDENTAL, SPECIAL OR PUNITIVE DAMAGES, ARISING FROM YOUR USE OF THE DATA.

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

The CAIDA UCSD Macroscopic Topology Dataset - < dates used >,
http://www.caida.org/tools/measurements/skitter

Users are encouraged, but not required, to include the following attribution in their acknowledgments section:

Support for the Macroscopic Topology Dataset is provided by the National Science Foundation, the US Department of Homeland Security, the WIDE Project, Cisco Systems, and CAIDA Members.

Please send any questions regarding skitter to skitter-info@caida.org.