Diogo Barradas

As of 2022, I am an Assistant Professor at the Cheriton School of Computer Science at the University of Waterloo, a member of the CrySP group, and a member of the Waterloo Cybersecurity and Privacy Institute.


I completed my PhD on Information Systems and Computer Engineering at Instituto Superior Técnico (IST) - Universidade de Lisboa, under the kind supervision of Prof. Luís Rodrigues and Prof. Nuno Santos. I conducted my research at the Distributed Systems Group at INESC-ID Lisboa. In late 2021, I was fortunate to become a postdoctoral fellow at the Department of Computer Science at Rice University under the supervision of Prof. Ang Chen.


Research Interests

My research is focused in network security and privacy, with particular emphasis on statistical traffic analysis and Internet censorship circumvention. I take additional interest in digital forensics.

Publications

Refereed Conference Publications

  • Secure and Efficient Group Handover Protocol in 5G Non-Terrestrial Networks.
    (ICC 2024) (to appear)
    Bohan Zhang, Peng Hu, Ahmad Akbari Azirani, Mohammad A. Salahuddin, Diogo Barradas, Noura Limam, Raouf Boutaba.
  • Flow Correlation Attacks on Tor Onion Service Sessions with Sliding Subset Sum.
    (NDSS 2024)
    Daniela Lopes, Jin-Dong Dong, Daniel Castro, Pedro Medeiros, Diogo Barradas, Bernardo Portela, João Vinagre, Bernardo Ferreira, Nicolas Christin, Nuno Santos.
  • NetShuffle: Circumventing Censorship with Shuffle Proxies at the Edge.
    (IEEE S&P 2024)
    Patrick Kon, Aniket Gattani, Dhiraj Saharia, Tianyu Cao, Diogo Barradas, Ang Chen, Micah Sherr, Benjamin E. Ujcich.
  • Stegozoa: Enhancing WebRTC Covert Channels with Video Steganography for Internet Censorship Circumvention.
    (Asia CCS 2022)
    Gabriel Figueira, Diogo Barradas, Nuno Santos.
  • Chinese Wall or Swiss Cheese? Keyword filtering in the Great Firewall of China.
    (TheWebConf 2021)
    Raymond Rambert, Zachary Weinberg, Diogo Barradas, Nicolas Christin.
  • FlowLens: Enabling Efficient Flow Classification for ML-based Network Security Applications.
    (NDSS 2021)
    Diogo Barradas, Nuno Santos, Luís Rodrigues, Salvatore Signorello, Fernando Ramos, André Madeira.
  • Poking a Hole in the Wall: Efficient Censorship-Resistant Internet Communications by Parasitizing on WebRTC.
    (CCS 2020)
    Diogo Barradas, Nuno Santos, Luís Rodrigues, Vítor Nunes.
  • Effective Detection of Multimedia Protocol Tunneling using Machine Learning.
    (USENIX Security 2018)
    Diogo Barradas, Nuno Santos, Luís Rodrigues.
  • Forensic Analysis of Communication Records of Web-based Messaging Applications from Physical Memory.
    (SECRYPT 2017)
    Diogo Barradas, Tiago Brito, David Duarte, Nuno Santos, Luís Rodrigues.

Refereed Journal Publications

  • Enhancing the Unlinkability of Circuit-Based Anonymous Communications with k-Funnels.
    (PACMNET/CoNEXT 2023)
    Vítor Nunes, José Brás, Afonso Carvalho, Diogo Barradas, Kevin Gallagher, Nuno Santos.
  • DeepSE-WF: Unified Security Estimation for Website Fingerprinting Defenses.
    (PoPETs 2023)
    Alexander Veicht, Cedric Renggli, Diogo Barradas.
  • Forensic Analysis of Communication Records of Messaging Applications from Physical Memory.
    (Computers & Security, Elsevier, 2018)
    Diogo Barradas, Tiago Brito, David Duarte, Nuno Santos, Luís Rodrigues.
  • DeltaShaper: Enabling Unobservable Censorship-resistant TCP Tunneling over Videoconferencing Streams.
    (PoPETs 2017)
    Diogo Barradas, Nuno Santos, Luís Rodrigues.

Refereed Workshop Publications

  • Connecting the Dots in the Sky: Website Fingerprinting in Low Earth Orbit Satellite Internet.
    (SpaceSec 2024) (pre-print)
    Prabhjot Singh, Diogo Barradas, Tariq Elahi, Noura Limam.
  • A First Look at Generating Website Fingerprinting Attacks via Neural Architecture Search.
    (WPES 2023)
    Prabhjot Singh*, Shreya Arun Naik*, Navid Malekghaini, Diogo Barradas, Noura Limam. (*co-first authors)
  • TIGER: Tor Traffic Generator for Realistic Experiments.
    (WPES 2023)
    Daniela Lopes, Daniel Castro, Diogo Barradas, Nuno Santos.
  • Rethinking Realistic Adversaries for Anonymous Communication Systems.
    (FOCI @ PETS 2023)
    Kevin Gallagher, Diogo Barradas, Nuno Santos.
  • Work in Progress: A Glance at Social Media Self-Censorship in North America.
    (STAST @ Euro S&P 2023)
    Wei Hu, Diogo Barradas.
  • Darwin's Theory Of Censorship: Analysing the Evolution of Censored Topics with Dynamic Topic Models.
    (WPES @ ACM CCS'22)
    Asim Waheed*, Sara Qunaibi*, Diogo Barradas, Zachary Weinberg. (*co-first authors)
  • Stargaze: A LEO Constellation Emulator for Security Experimentation.
    (CPSIoTSec @ ACM CCS'22)
    Patrick Tser Jern Kon, Diogo Barradas, Ang Chen.
  • The Nuts and Bolts of Building FlowLens.
    (LASER @ NDSS 2021)
    Diogo Barradas, Nuno Santos, Luís Rodrigues, Salvatore Signorello, Fernando Ramos, André Madeira.
  • Towards a Scalable Censorship-Resistant Overlay Network based on WebRTC Covert Channels.
    (DICG @ ACM/IFIP Middleware'20)
    Diogo Barradas, Nuno Santos.
  • On the unobservability of multimedia-based covert channels for Internet censorship circumvention.
    (ISOC.PT ANRW 2020)
    Diogo Barradas, Nuno Santos, Luís Rodrigues.
    Best Research Paper and Internet Impact Acknowledge Mention
  • Assessing the Feasibility of Machine Learning to Detect Network Covert Channels.
    (EuroSys Doctoral Workshop 2018)
    Diogo Barradas.

Technical Reports, Posters, and National Conference Publications

  • The Spectre of Surveillance and Censorship in Future Internet Architectures.
    (arXiv preprint 2024)
    Michael Wrana, Diogo Barradas, N. Asokan.
  • On the Feasibility of Fingerprinting Collaborative Robot Traffic.
    (arXiv preprint 2023)
    Cheng Tang, Diogo Barradas, Urs Hengartner, Yue Hu.
  • User Sessions on Tor Onion Services: Can Colluding ISPs Deanonymize Them at Scale?.
    (Poster @ ACM CCS'22)
    Daniela Lopes, Pedro Medeiros, Jin-Dong Dong, Diogo Barradas, Bernardo Portela, João Vinagre, Bernardo Ferreira, Nicolas Christin, Nuno Santos.
  • Identificação de Canais Encobertos no Skype usando Esboços em SDNs.
    (INForum 2019)
    André Madeira, Diogo Barradas, Nuno Santos, Luís Rodrigues.
    Best paper award
  • Síntese de Vídeo para Evasão de Censura na Internet.
    (INForum 2016)
    Diogo Barradas, Nuno Santos, Luís Rodrigues.

Theses

  • Unobservable Multimedia-based Covert Channels for Internet Censorship Circumvention.
    Diogo Barradas (supervised by Professors Luís Rodrigues and Nuno Santos)
    PhD. Thesis, IST, Universidade de Lisboa, July 2021.
  • Unobservable Covert Streaming for Internet Censorship Circumvention.
    Diogo Barradas (supervised by Professors Luís Rodrigues and Nuno Santos)
    MSc. Thesis, IST, Universidade de Lisboa, September 2016.

Teaching / Supervising

Courses: Current Students:
  • Shreya Arun Naik - MMath @ U. Waterloo
  • Sina Kamali - MMath @ U. Waterloo
  • Michael Wrana (co-advisor: N. Asokan) - CS PhD @ U. Waterloo
Past Students:
  • Adrian Cruzat La Rosa - MMath @ U. Waterloo (Jan. 2024)
  • Prabhjot Singh - MMath @ U. Waterloo (Jan. 2024)
  • Norhan Abbas (co-advisor: Mei Nagappan) - MMath @ U. Waterloo (Sep. 2023)
  • Afonso Carvalho (co-advisor: Nuno Santos) - MSc. @ U. Lisbon (Nov. 2022)
  • Francisco Silva (co-advisor: Nuno Santos) - MSc. @ U. Lisbon (Nov. 2022)
  • José Brás (co-advisor: Nuno Santos) - MSc. @ U. Lisbon (Nov. 2022)

Service

  • Program committee: CCS 2024, TheWebConf 2024, CCS 2023, PETS 2023, RAID 2023, NSS 2023, MetaCom 2023, FOCI 2022, IEEE DSC 2022, PETS 2022, ICICS 2022, SECRYPT 2022, PETS 2021, ICICS 2021, SECRYPT 2021
  • Program co-chair: FFSPIN @ SIGCOMM 2022
  • Shadow program committee: IEEE S&P 2021

Additional Experience

  • 2021 PostDoc fellow at Rice University (Oct-Nov)
    I was a postdoctoral fellow at the Department of Computer Science at the University of Rice under the supervision of Prof. Ang Chen. During my visit, we geared efforts towards the bootstrap of novel privacy-preserving mechanisms for emerging networking environments.
  • 2020 Short-Term Research Scholar at Carnegie Mellon University (Fev-Aug)
    I collaborated with Professor Nicolas Christin at CMU's CyLab Security & Privacy Institute. My research project focuses on the measurement and understading of Internet censorship conducted by state-level actors.
  • 2019 - 2017 Teaching Assistant - Instituto Superior Técnico
    2018/19 Fall Semester - Forensics Cyber-Security
    2017/18 Fall Semester - Network and Computer Security
  • 2018 CRYPTACUS Training School
    I have attended the Training School on Cryptanalysis of Ubiquitous Computing Systems. The program has focused the assessment of theoretical and practical cryptographic mechanisms designed to ensure security and privacy.
  • 2017 Summer Internship in Advanced Computing Research at the University of Texas at Austin
    I have studied the application of machine learning techniques to the problem of gesture recognition. My internship was supervised by Professor Lili Qiu.

Contact

Location:

Office: DC 2631
University of Waterloo
200 University Ave W
Waterloo, Ontario, Canada
N2L 3G1