My research interests are in network measurement and anti-abuse for improved stability and security of the Internet. I lead the Internet Measurement and Anti-Abuse Laboratory (IMAAL). Our research includes (but is not limited to) the following areas:

  • DNS/DNSSEC deployment and measurement
  • IPv6 deployment and measurement
  • DDoS prevention and mitigation techniques


  • Our paper on discovering and measuring a vulnerability in libspf2 was recently accepted to IMC 2022!
  • Our paper on SPF validation was recently accepted to CoNEXT 2021!
  • Profs. Bryant and O'Hallaron at CMU recently featured in a blog post the little Computer Systems-based song I wrote and performed with some BYU Computer Science students.

Recent Publications

Conference Proceedings

  • Alden Hilton, Casey Deccio, and Jacob Davis. Fourteen Years in the Life: A Root Server's Perspective on DNS Resolver Security. USENIX Security 2023.
  • Casey Deccio. W-Bad: Interception, Inspection, and Interference with Web Proxy Auto-Discovery (WPAD). TMA 2023.
  • Protick Bhowmick, Ishtiaq Ashiq, Casey Deccio, and Taejoong Chung. TTL Violation of DNS Resolvers in the Wild. PAM 2023.
  • Nathaniel Bennett, Rebekah Sowards, and Casey Deccio. SPFail: Discovering, Measuring and Remediating Vulnerabilities in Email Sender Validation. IMC 2022.
  • Ramin Yazdani, Alden Hilton, Jeroen van der Ham, Roland van Rijswijk-Deij, Casey Deccio, Anna Sperotto, Mattijs Jonker. Mirrors in the Sky: On the Potential of Clouds in DNS Reflection-based Denial-of-Service Attacks. RAID 2022.
  • Casey Deccio, Tarun Yadav, Nathaniel Bennett, Alden Hilton, Michael Howe, Tanner Norton, Jacob Rohde, Eunice Tan, and Bradley Taylor. Measuring Email Sender Validation in the Wild. CoNEXT 2021.
  • Jacob Davis and Casey Deccio. Advertising DNS Protocol Use to Mitigate DDoS Attacks. ICNP 2021.
  • Jacob Davis and Casey Deccio. A Peek Into the DNS Cookie Jar: An Analysis of DNS Cookie Use. PAM 2021.
  • Casey Deccio, Alden Hilton, Michael Briggs, Trevin Avery, and Robert Richardson. Behind Closed Doors: A Network Tale of Spoofing, Intrusion, and False DNS Security. IMC 2020.
  • Casey Deccio and Jacob Davis. DNS Privacy in Practice and Preparation. CoNEXT 2019.
  • Jonathan Demke and Casey Deccio. On DNSSEC Negative Responses, Lies, and Zone Size Detection. PAM 2019.
  • Casey Deccio. DNS Diagnostics through the Eye of the Beholder. ICNC 2019 NAPE.
  • Casey Deccio, Derek Argueta, and Jonathan Demke. A Quantitative Study of the Deployment of DNS Rate Limiting. ICNC 2019 CIS.
  • Casey Deccio, Jeff Sedayao, Krishna Kant, Prasant Mohapatra. Quantifying and Improving DNSSEC Availability. ICCCN 2011.
  • Casey Deccio, Jeff Sedayao, Krishna Kant, Prasant Mohapatra. Measuring Availability in the Domain Name System. IEEE INFOCOM 2010.
  • Casey Deccio, Chao-Chih Chen, Jeff Sedayao, Krishna Kant, Prasant Mohapatra. Quality of Name Resolution in the Domain Name System. IEEE ICNP 2009.
  • Casey Deccio, Joseph Ekstrom, Charles Knutson, D. Ryan Partridge, Kevin Tew. A Study of the Suitability of IrOBEX for High-Speed Exchange of Large Data Objects. GLOBECOM 2003.

Journal Articles

  • Alden Hilton, Joel Hirschmann, and Casey Deccio. Beware of IPs in Sheep's Clothing: Measurement and Disclosure of IP Spoofing Vulnerabilities. IEEE/ACM Transactions on Networking. Feb 2022.
  • Casey Deccio. Maintenance, Mishaps and Mending in Deployments of the Domain Name System Security Extensions (DNSSEC). International Journal of Critical Infrastructure Protection. Jul 2012.
  • Casey Deccio, Jeff Sedayao, Krishna Kant, Prasant Mohapatra. Quantifying DNS Namespace Influence. Computer Networks. Feb 2012.

Books and Book Chapters

  • Krishna Kant, Casey Deccio. Security and Robustness in the Internet Infrastructure. In Handbook on Securing Cyber-Physical Critical Infrastructure. Morgan Kaufman (2012), Waltham, MA. pp. 705-733.
  • Casey Deccio. Quantifying and Improving DNS Availability. PhD Dissertation. University of California Davis, 2010.


  • Comcast. We gratefully acknowledge Comcast for generous sponsorship from the Comcast Innovation Fund in 2019, 2020, and 2021.
  • Verisign. We gratefully acknowledge VeriSign, Inc., for the grant used to support our research (2019, 2020, 2021).


Current Students

  • Tyler Dean (MS)
  • Grant MacGregor (BS)
  • Jonah Simmons (BS)
  • Anika Taylor (BS)
  • McKynlee Wilson (BS)

Past Students

  • Tyler Karren (MS 2023)
  • Jake Mullins (BS)
  • Darren Skidmore (BS)
  • Russell Dupaix (BS)
  • Dallan Adamson (BS)
  • Davis Forster (BS)
  • Nathaniel Bennett (BS)
  • Jamison Lofthouse (BS)
  • Nathan Larsen (BS)
  • Jackie Hu (BS)
  • Rebekah Sowards (BS)
  • Nathan Craddock (BS)
  • Eric Spencer (BS)
  • Trevin Avery (MS 2021)
  • Alden Hilton (BS, MS 2021)
  • Jacob Davis (BS, MS 2021)
  • Joel Hirschmann (BS)
  • Jason Anderson (BS)
  • Kimball Leavitt (BA, MS)
  • Michael Howe (BS)
  • Bradley Taylor (BS)
  • Leah Roberts (Honors Thesis 2021)
  • Evan Smith (BS)
  • Alyssa Rogers (BS)
  • Michael Briggs (BS)
  • Torsten Gang (BS)
  • Xin Zhao (BS)
  • Johnny Huang (BS)
  • Jacob Rohde (BS)
  • Kwan Ko (BS)
  • Ethan Rowe (BS)
  • Tyler Brady (BS)
  • Shawn Li (BS)
  • Charles Tolley (BS)
  • Tanner Norton (BS)
  • Cade Daniel (BS)
  • Luke Summers (BS)
  • Kenneth Stocks (BS)
  • Darren Remund (BS)
  • Derek Argueta (BS)
  • Jack Demke (BS)
  • Eunice Tan (MS 2018)


  • CS 324 - Fall 2023
  • CS 324 - Winter 2023
  • CS 460 - Fall 2022
  • CS 660 - Winter 2022
  • CS 324 - Winter 2022
  • CS 460 - Fall 2021
  • CS 324 - Winter 2021
  • CS 660 - Winter 2021
  • CS 142 - Fall 2020
  • CS 460 - Fall 2020
  • CS 660 - Winter 2020
  • CS 324 - Winter 2020
  • CS 460 - Fall 2019
  • CS 660 - Winter 2019
  • CS 324 - Winter 2019
  • CS 460 - Fall 2018
  • CS 324 - Winter 2018
  • CS 460 - Fall 2017
  • CS 360 - Winter 2017


Dr. Casey Deccio is an Associate Professor in the Computer Science Department at Brigham Young University (BYU). He earned B.S. and M.S. degrees in Computer Science from BYU in 2002 and 2004, respectively, and received a Ph.D. from UC Davis, in Computer Science, in 2010.

Prior to coming to BYU, Dr. Deccio was a Senior Research Scientist at Verisign Labs since 2014, where his research included DNS ecosystem tools, monitoring, measurement, and modeling, with the objective of increasing stability, security, and safety of the Internet. Before that he was a Principal Research and Development Cyber Security Staff member at Sandia National Laboratories, where he had been employed since 2004 and where he was responsible for network-related research and development, including DNSSEC and IPv6 deployment efforts. While at Sandia he developed DNSViz, the widely used tool for DNS analysis and visualization. He also served as an ICANN Research Fellow supporting the Security and Stability Advisory Committee (SSAC) in 2013.

Outside of work, he enjoys making music and participating in recreational activities with his wife and five children.


I sing barbershop with a number of BYU Computer Science students in a group called Sing++. Here is a musical tribute to my systems class.