Dasu -- A platform for measurement experimentation and broadband characterization

The short story

Dasu is a measurement experimentation platform for the Internet's edge. It supports both controlled network experimentation and broadband characterization, building on public interest on on the later to gain the adoption necessary for the former.

Do you ever wonder what your ISP service is really like? Are you getting your money's worth? How do DNS public services perform compared with those of your own ISP - in the long run?

Some Internet Service Providers (ISPs) set complex policies based on time of day, service level or application; others are known to over-subscribe their networks, actively shape traffic or even discourage heavy hitters. To you, the end user, these policies translate into noticeable time-of-day variations on bandwidth availability, limited performance for specific applications, or simply overall degradation of the quality of service received. As a consumer you want to be sure that you are getting the service that you're paying for and are informed of any network management practices that impact your performance. The main goal of Dasu is to efficiently capture these variations by constantly monitoring and measuring the level of service provided by your ISP, so that you can make informed decisions about your choice of service provider.

Dasu does this by constantly analyzing your performance and results from limited light-weight measurement experiments to, among other things, detect problems and infer the presence of practices that negatively impact network performance.

The Dasu plugin, which seamlessly installs into the Vuze/Azureus BitTorrent client, can be downloaded >>>here<<<.

Join our many users and install dasu today!

Dasu standalone is here!

  • Don't use BitTorrent? No problem, you can get all the benefits of Dasu by downloading our standalone client. The standalone Dasu client is in beta version!.
  • It quitely sits on your status bar and monitors your ISP performance. To see what's going on simply click on the icon for more details.
  • Want to help us improve Dau? Be a beta tester! Simply download one of the installers below and let us know what you think.
  • We are acively working on improving Dasu and will push new updates to you automatically. Things are about to get interesting!
  • Beta Standalone Version

    • Microsoft Windows: Installer
    • Mac OS X v10.5+: dmg
    • Source: please contact us at This email address is being protected from spambots. You need JavaScript enabled to view it.

    Coverage map

    In the news

    • 4/5/2011: Ars Technica wrote about our analysis of BitTorrent usage during the recent Japanese earthquake and Internet shutdowns in Egypt and Libya.


  • 4/24/2013: Vesion 5.0 on beta testers.
  • 1/15/2013: Vesion 4.11 released.
  • 10/25/2012: Vesion 4.0 released.
  • 4/9/2011: Version 3.0 released.
  • 3/29/2011: Version 3.0 on beta testers.
  • 11/05/2010: Fix 4510 incompatability.
  • 11/03/2010: Version 2.0 released.
  • 5/30/2010: First version (1.0) released.
  • Version Control

  • 4.11: Prevent loss of window focus on Windows during test execution.
  • 4.10: Bug fixes!
  • 4.02: Couple last bug fixes before going live.
  • 4.01: Minor bug fixed from initial beta testing.
  • 4.00: Latest evolution in Dasu.
  • 3.02: Fix to run with
  • 3.01: Bug fixes.
  • 3.0: Major rewrite! Check it out.
  • 2.02: Fix data collection bug.
  • 2.01: Fix 4510 incompatability.
  • 2.0: Detection of more types of interference.
  • 1.0: Fixed a few final bugs before public release.
  • 0.99: Fixed some bugs and updated with correct server urls.
  • 0.96: Initial release.
  • For the technical crowd

    Most previous work aimed at characterizing ISP performance perceived by end users focuses on performing one-time active measurements from user-triggered benchmarking tools - this only allows them to capture snapshots of the network properties they measure. A key drawback of these techniques is that they are unable to capture service variations or characterize sporadic events because of the transient nature of such occurrences. Furthermore, many of these tools only focus on specific types of metrics or services: upload/download limits, DNS performance, HTTP caches.

    Ideally, ISP characterization should be performed (i) at scale, to capture the diversity of available providers and their services; (ii) continuously, to capture dynamic changes due to network management policies (e.g. traffic shaping or oversubscribed networks) and unscheduled events (e.g. service interruptions); and (iii) from end users, to guarantee accurate characterization of service.

    While there has been much progress toward this, existing approaches exhibit an apparently unavoidable trade-off between coverage, continuous monitoring and capturing user-perceived performance. We argue that network-intensive applications running on end systems (such as BitTorrent) avoid these tradeoffs, offering an ideal platform for ISP characterization.

    By passively monitoring user-generated traffic within BitTorrent, Dasu is able to capture the end user's view in a scalable manner. By combining passive monitoring with dynamically extensive, on demand, active measurements, Dasu can achieve the effectiveness of hardware-based solutions (e.g. SamKnows/FCC), without their associated costs, while retaining the control, flexibility, and low-barrier to adoption of software-based models.

    Why Dasu?

    Dasu is the Japanese general word for 'putting something out there' or 'showing something'. It is mainly used to signify 'showing secrets'.




    • Mario A. Sánchez, John S. Otto, Zachary S. Bischof, David R. Choffnes, Fabián E. Bustamante, Balachander Krishnamurthy and Walter Willinger. Dasu: Pushing Experiments to the Internet's Edge, In Proc. of the USENIX Symposium on Networked Systems Design and Implementation (NSDI), April 2013.
    • Mario A. Sánchez, John S. Otto, Zachary S. Bischof, and Fabián E. Bustamante. Trying Broadband Characterization at Home. In Proc. of the Passive and Active Measurement Conference (PAM), March 2013.
    • Zachary S. Bischof, John S. Otto, and Fabián E. Bustamante. Up, Down and Around the Stack: ISP Characterization from Network Intensive Applications. In Proc. of ACM SIGCOMM Workshop on Measurements Up the STack (W-MUST), August 2012. Also in ACM SIGCOMM CCR Special Issue, Volume 42 Issue 4, October 2012.
    • Zachary S. Bischof, John S. Otto, Mario A. Sánchez, John P. Rula, David R. Choffnes, and Fabián E. Bustamante . Crowdsourcing ISP Characterization to the Network Edge. In Proc. ACM SIGCOMM Workshop on Measurements Up the STack (W-MUST), August 2011.
    • Mario A. Sánchez, David R. Choffnes and Fabián E. Bustamante. Heuristics for passively detecting interference from peers in P2P systems. Tech. Report NWU-EECS-09-23, Northwestern University, May 2009.



    Frequently asked questions

    • Why use the Vuze/Azureus BitTorrent client? For one, it's probably the most popular client in terms of use, so targeting Vuze gives us the greatest potential impact. Additionally, Vuze is Java-based, meaning anyone can run their software (and ours). Finally, Vuze offers a convenient plugin feature, requiring no changes to your existing Vuze client. And once you're running Dasu, it will automatically search for new versions and update itself for you!
    • Does this work with my operating system? In short, yes. Dasu relies only on Vuze, so it should work anywhere that Vuze works. If you encounter a problem, please let us know!

    Take a test-drive of the Dasu interface >>>here<<<.

    Watch a screencast showing how to install and use Dasu:

    Translators: If you're interested in translating Dasu messages into another language, contact us at This email address is being protected from spambots. You need JavaScript enabled to view it. .

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