ACM SIGCOMM 2021, virtually (online)

ACM SIGCOMM 2021 Workshop on Free and Open Communications on the Internet (FOCI 2021)

In Cooperation With USENIX


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Workshop program

  • Friday, August 27, 2021 ET

  • 1:00 - 1:10 pm ET      Opening Remarks

  • 1:00 - 1:10 pm ET

    Opening Remarks

    Speakers: Workshop Chairs

  • 1:10 - 1:45 pm ET      Session 1: Blocking

    Session chair: Nguyen Phong Hoang (Stony Brook University / Citizen Lab)
  • A multi-perspective view of Internet censorship in Myanmar

    Ramakrishna Padmanabhan (CAIDA, UC San Diego); Arturo Filastò, Maria Xynou (OONI); Ram Sundara Raman (University of Michigan); Kennedy Middleton (UC San Diego); Mingwei Zhang (CAIDA, UC San Diego); Doug Madory (Kentik); Molly Roberts (UC San Diego); Alberto Dainotti (CAIDA, UC San Diego)

  • Measuring QQMail's automated email censorship in China

    Jeffrey Knockel, Lotus Ruan (Citizen Lab, University of Toronto)

  • 1:45 - 1:55 pm ET Coffee/Tea break

  • 1:55 - 2:30 pm ET      Session 2: Detection

    Session chair: Kevin Bock (University of Maryland)
  • On the state of V3 onion services

    Tobias Höller, Michael Roland, René Mayrhofer (Johannes Kepler University Linz)

  • Exploring Simple Detection Techniques for DNS-over-HTTPS Tunnels

    Carmen Kwan, Paul Janiszewski, Shela Qiu, Cathy Wang (University of Waterloo); Cecylia Bocovich (Tor Project)

  • 2:30 - 2:40 pm ET Coffee/Tea break

  • 2:40 - 3:15 pm ET      Session 3: HTTPS Censorship

    Session chair: Ram Sundara Raman (University of Michigan)
  • Even Censors Have a Backup: Examining China’s Double HTTPS Censorship Middleboxes

    Kevin Bock, Gabriel Naval, Kyle Reese, Dave Levin (University of Maryland)

  • BlindTLS: Circumventing TLS-based HTTPS censorship

    Sambhav Satija (University of Wisconsin-Madison); Rahul Chatterjee (University of Wisconsin)

  • 3:15 - 3:25 pm ET Coffee/Tea break

  • 3:25 - 3:45 pm ET      Session 4: Mis/Disinformation

    Session chair: TBA
  • Interactions with Potential Mis/Disinformation URLs Among U.S. Users on Facebook, 2017-2019

    Aydan Bailey, Theo Gregersen, Franziska Roesner (University of Washington)

  • 3:45 - 3:55 pm ET Coffee/Tea break

  • 3:55 - 4:55 pm ET      Panel: Practical Perspectives on Censorship

  • 3:55 - 4:55 pm ET

    Panel chairs: Dave Levin (University of Maryland), Eric Wustrow (University of Colorado Boulder)

         Nima Fatemi (Kandoo)
         Xiaokang Wang (V2Ray|V2Fly Lead Developer)
         Cecylia Bochovich (The Tor Project)

  • 4:55 - 5:00 pm ET      Closing Remarks

  • 4:55 - 5:00 pm EDT

    Closing Remarks

    Speaker(s): Workshop Chairs

Call for Papers

The 11th Workshop on Free and Open Communications on the Internet (FOCI '21) will bring together researchers and practitioners who study and develop technologies that affect digital speech online. FOCI will examine three broad areas of digital speech: censorship, surveillance, and disinformation/strategic communication. We solicit contributions from the fields of computer science, the social sciences, and law, and we welcome interdisciplinary submissions.

The goal of FOCI is to catalyze new research directions and discussions that might not be mature or established enough to appear at conventional computer science measurement and security conferences. We aim to foster the development of early-stage work across disciplines. We recognize that control over online speech has become inherently interdisciplinary, so that studying these problems often involves adopting a holistic, interdisciplinary perspective.

All papers accepted to FOCI'21 will be published as open access under the ACM Digital Library free of charge to the authors.

Topics of Interest

We welcome studies on all aspects of digital speech control. This includes (but is not limited to) the measuring, building, and deploying of:

  • Anonymity systems
  • Censorship systems
  • Circumvention systems
  • Content moderation systems (e.g., social media)
  • Corporate or government surveillance
  • Digital propaganda
  • Disinformation and misinformation online
  • Laws and policies governing communication and surveillance
  • Press freedom
  • Societal and behavioral impacts of censorship and surveillance

Submission Instructions

Papers must be submitted via the submission site, and can fall into one of two tracks:

Technical Track: Submitted papers must be no longer than six pages (excluding references and appendices), based on the standard SIGCOMM format. Please note, however, that reviewers are not required to read appendices, and papers should be able to stand on their own without them. More specifically:

  • Papers must be formatted for printing on Letter-sized (8.5" by 11") paper. Paper text blocks must follow ACM guidelines: double-column, with each column 9.25" by 3.33", 0.33" space between columns. Each column must use 10-point font or larger, and contain no more than 55 lines of text.
  • If you are using LaTeX, you may make use of this template for ACM conference proceedings. With the older versions of this template you must add "10pt" to the documentclass command to meet the submission requirements. The current template sets 10pt by default. (Unlike the official template, it only includes an example for conference proceedings.)

Law/Social Science Track: Papers submitted in this track must be no longer than 15 pages based either on the standard SIGCOMM format (as above) or, if preferable, 15 single-spaced pages using normal 8.5" x 11" format pages. Shorter papers are encouraged where possible, though organizers will be more flexible on page count with this track, granting exceptions on a case-by-case basis. References will not count towards the page limit. This track aims to encourage submissions from fields such as law, economics, and public policy, where longer articles are traditional.

Technically-focused papers submitted to either track may be desk-rejected if they exceed the page limit for technical papers.

FOCI '21 will be double-blind, and so all papers must be properly anonymized; no author names or affiliations may appear on the title page, and authors should avoid revealing their identities in the text. When referring to your previous work, do so in the third person, as though it were written by someone else. Only blind the reference itself in the (unusual) case that a third-person reference is infeasible. Papers accompanied by nondisclosure agreement forms will not be considered. Accepted submissions will be treated as confidential prior to publication on the FOCI '21 website; rejected submissions will be permanently treated as confidential.

Simultaneous submission of the same work to multiple venues, submission of previously published work, or plagiarism constitutes dishonesty or fraud. Note, however, that we expect that many working papers accepted for FOCI '21 will eventually be extended as full papers suitable for formal academic publication and presentation at future conferences, and such papers are eligible for submission to FOCI.

Papers that do not comply with the submission requirements, including length and anonymity, may be rejected without review.

Please do not hesitate to contact the program co-chairs at if you have any questions about the submission process or other aspects of FOCI '21.

Important Dates

  • May 13, 2021
    May 20, 2021, 11:59:59pm PDT

    Submission deadline

  • June 11, 2021

    Acceptance notification

  • July 2, 2021

    Camera-ready deadline

  • August 27, 2021

    Workshop day

Program Committee

  • Program Chairs
  • Dave Levin

    University of Maryland

  • Eric Wustrow

    University of Colorado Boulder

  • Program Committee
  • Alan Mislove

    Northeastern University

  • Alberto Dainotti

    CAIDA, UC San Diego

  • Amir Houmansadr

    UMass Amherst

  • Anita Nikolich

    University of Illinois at Urbana Champaign

  • Arturo Filastò

    Open Observatory of Network Interference (OONI)

  • Blase Ur

    University of Chicago

  • Cecylia Bocovich

    Tor Project

  • Dan Wallach

    Rice University

  • Drew Springall

    Auburn University

  • Kevin Bock

    University of Maryland

  • Liang Wang

    Princeton University

  • Masashi Crete-Nishihata

    Citizen Lab

  • Michael Carl Tschantz

    International Computer Science Institute

  • Nguyen Phong Hoang

    Stony Brook University

  • Philipp Winter

    Brave Research

  • Rachee Singh

    Microsoft Research

  • Rachel Greenstadt

    New York University

  • Ram Sundara Raman

    University of Michigan

  • Reethika Ramesh

    University of Michigan

  • Rishab Nithyanand

    University of Iowa

  • Rob Jansen

    U.S. Naval Research Laboratory

  • Roger Dingledine

    Tor Project

  • Roya Ensafi

    University of Michigan

  • Tariq Elahi

    University of Edinburgh

  • Will Scott

    Protocol Labs