Amy Babay

image of Amy Babay

Department of Computer Science
Johns Hopkins University

Malone 207
3400 North Charles Street
Baltimore, MD 21218

babay (at)

I am currently a fourth-year PhD student in Computer Science at Johns Hopkins University, where my advisor is Yair Amir. I am a member of the Distributed Systems and Networks lab.

I completed my Masters in Computer Science in May 2014 at Johns Hopkins and worked at LTN Global Communications before starting my PhD. I received my B.A. in Cognitive Science from Johns Hopkins in May 2012. As an undergraduate, I was a research assistant in the Language Acquisition lab. For more information about my experiences, see my resume.


A New Generation of Internet Services

I am working toward supporting a new generation of Internet services using structured overlay networks. This broad vision is outlined in an ICDCS 2017 vision track paper that describes how services that require highly demanding combinations of latency, reliability, resilience, and processing can be realized using the structured overlay concept.

My most recent work focuses on services with extremely low latency requirements (e.g. remote manipulation). This video shows me interacting with a Phantom Omni haptic device over a wide-area network. The signal from each device is sent halfway across the US before being sent back to the other device, so the latency is as if one device is on the East coast and the other is on the West coast. You can hear this latency when I tap on the desk. My work in this area aims to enable such low-latency communication and interaction with high reliability.

To support such applications, we have developed new overlay dissemination protocols that send messages over a subgraph of an overlay topology (a dissemination graph) to provide the necessary timeliness and reliability. This includes work with Emily Wagner, Michael Dinitz, and Yair Amir on constructing dissemination graphs that provide a good tradeoff between reliability and cost, which was selected for the best paper award at ICDCS 2017.

Before starting my PhD, I gained exposure to global-scale overlay technologies in the commercial world at LTN Global Communications. LTN is a cloud service provider that operates global overlay networks, transporting live video for the TV and media industries.

Intrusion-Tolerant SCADA for the Power Grid

I am interested in building dependable infrastructure, or networked systems that maintain correct operation and predictable performance, even in the presence of partial failures or compromises. I am currently working on applying intrusion-tolerant principles to create SCADA systems for the power grid that can continue to operate correctly and at their required levels of performance even when part of the system has been compromised by a sophisticated attacker. We have recently released version 1.0 of the Spire intrusion-tolerant SCADA system, which is designed to withstand malicious attacks at both the network level and the system level. Spire successfully withstood a red team attack conducted by Sandia National Laboratories at Pacific Northwest National Laboratory (PNNL) from March 27 to April 7, 2017.

I am additionally interested in consistent state maintenance in the presence of failures, including approaches such as Paxos and Extended Virtual Synchrony, as well as resilient (including intrusion-tolerant) systems more generally.

Accelerated Ring Protocol

I developed a reliable, ordered multicast protocol based on a logical token ring that improves the state-of-the-art performance on 1-gigabit and 10-gigabit local area networks. The Accelerated Ring protocol circulates the token more quickly, reducing the impact of latency due to buffering and allowing for controlled parallelism in sending. I incorporated the Accelerated Ring protocol into the messaging protocol of the Spread Toolkit. A version of Spread that includes this protocol was released as an experimental version in July 2013, and the Accelerated Ring protocol is the toolkit's standard protocol for data center environments as of version 4.4.0.

Honors and Awards

IEEE ICDCS 2017 Best Paper Award (June 2017): Our paper Timely, Reliable, and Cost-effective Internet Transport Service using Dissemination Graphs was selected as the best paper out of 531 submissions.

Computer Science Department Special Service Award (May 2015): for "outstanding work to benefit the department, Johns Hopkins University, and the community."

Excellence in Cognitive Science Award (May 2012): awarded annually to a graduating Cognitive Science major for academic excellence and outstanding accomplishment in research.


Conference Papers

ICDCS 2017: Amy Babay, Emily Wagner, Michael Dinitz, and Yair Amir, "Timely, Reliable, and Cost-Effective Internet Transport Service using Dissemination Graphs," in Proceedings of the IEEE 37th International Conference on Distributed Computing Systems, Atlanta, GA, June 2017, pp. 1-12, DOI 10.1109/ICDCS.2017.63. Best paper [PDF, IEEEXplore]

ICDCS 2016: Amy Babay and Yair Amir, "Fast Total Ordering for Modern Data Centers," in Proceedings of the IEEE 36th International Conference on Distributed Computing Systems, Nara, Japan, June 2016, pp. 669-679, DOI 10.1109/ICDCS.2016.20 [PDF, Extended Technical Report, IEEEXplore]

ICDCS 2016: Daniel Obenshain, Thomas Tantillo, Amy Babay, John Schultz, Andrew Newell, Md. Endadul Hoque, Yair Amir, and Cristina Nita-Rotaru, "Practical Intrusion-Tolerant Networks," in Proceedings of the IEEE 36th International Conference on Distributed Computing Systems, Nara, Japan, June 2016, pp. 45-56, DOI 10.1109/ICDCS.2016.99 [PDF, Earlier Technical Report, IEEEXplore]

Invited Papers

ICDCS 2017 (Vision Track): Amy Babay, Claudiu Danilov, John Lane, Michal Miskin-Amir, Daniel Obenshain, John Schultz, Jonathan Stanton, Thomas Tantillo, and Yair Amir, "Structured Overlay Networks for a New Generation of Internet Services," in Proceedings of the IEEE 37th International Conference on Distributed Computing Systems, Atlanta, GA, June 2017, pp. 1771-1779, DOI 10.1109/ICDCS.2017.119 [PDF, IEEEXplore]

Posters and Student Forum Papers

DSN 2015 Student Forum: Amy Babay, "Timely, Reliable, and Cost-effective Transport Service using Dissemination Graphs," IEEE International Conference on Dependable Systems and Networks (Student Forum), Rio de Janeiro, Brazil, 2015. [PDF]

ICDCS 2015 Poster: Amy Babay and Yair Amir, "Fast Total Ordering for Modern Data Centers," in Proceedings of the IEEE 35th International Conference on Distributed Computing Systems, Columbus, OH, June 2015, pp. 762-763, DOI 10.1109/ICDCS.2015.97 [Poster, Extended Abstract, IEEEXplore]


Masters Thesis: Amy Babay, The Accelerated Ring Protocol: Ordered Multicast for Modern Data Centers, Master's thesis, Johns Hopkins University, Baltimore, MD, May 2014. [PDF]

Patent Applications

Yair Amir, Amy Babay, and Thomas Tantillo, "Systems and Methods for Cloud-Based Control and Data Acquisition with Abstract State," United States Provisional Patent Application 62/451,341, filed January 2017.

Yair Amir, Amy Babay, and Thomas Tantillo, "Network-Attack-Resilient Intrusion-Tolerant SCADA Architecture," International Patent Application PCT/US17/38565, filed June 2017.


Co-instructor (with Yair Amir) for Software for Resilient Communities (CS310): Spring 2018.

Co-instructor (with Yair Amir) for Intermediate Programming (CS120): Fall 2013, Spring 2014, Fall 2015.

Special help for Distributed Systems (CS437): Fall 2012, Fall 2014.