Computer Engineering Seminar Series

April 19, 2024 ececosem

When research comes full circle: A missed opportunity and what to learn from it

In this reprisal of my keynote address at ACM CCS 2023, I will discuss user-authentication practice on the Internet and the development of the research community’s apathy toward it in the 2000s. While we were focusing on replacing passwords (versus improving their use), industry leaders by the late 2010s were decrying password reuse across accounts as the “No. 1 cause of harm on the Internet” and the cause of “99% of compromised accounts”.
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November 22, 2023 ececosem

Resource Efficient Large Scale ML: Plan Before You Run

As ML on structured data becomes prevalent across enterprises, improving resource efficiency is crucial to lower costs and energy consumption. Designing systems for learning on structured data is challenging because of the large number of models. Parameters and data access patterns. We identify that current systems are bottlenecked by data movement which results in poor resource utilization and inefficient training.
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September 28, 2023 ececosem

Fair and Optimal Prediction via Post-Processing

To mitigate the bias exhibited by machine learning models, fairness criteria can be integrated into the training process to ensure fair treatment across all demographics, but it often comes at the expense of model performance. Understanding such tradeoffs, therefore, underlies the design of optimal and fair algorithms. In this talk, I will first discuss our recent work on characterizing the inherent tradeoff between fairness and accuracy in both classification and regression problems, where we show that the cost of fairness could be characterized by the optimal value of a Wasserstein-barycenter problem. Then I will show that the complexity of learning the optimal fair predictor is the same as learning the Bayes predictor and present a post-processing algorithm based on the solution to the Wasserstein-barycenter problem that derives the optimal fair predictors from Bayes score functions
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August 23, 2023 ececosem

Resiliency and Efficiency of Complex Enterprise Systems

Modern cloud-based applications adhere to a microservices architecture, encompassing numerous components interconnected through intricate dependencies, operating within a distributed environment. This talk gives an overview of three recent research projects aimed at solving practical challenges in promptly identifying and diagnosing outages.
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March 29, 2023 ececosem

The Past, Present, and Future of High-Performance Computing

Emphasis on next-generation computing is driven at the national level because it affects scientific discovery, engineering, healthcare, security, and economic competitiveness. Moreover, high-performance computing is playing a greater role in our daily activities, requiring more performance from each system. However, pushing the performance envelope is becoming increasingly challenging – designing a machine that is 5ox faster isn’t as simple as making today’s machines sox larger. The future of high-performance computing will incorporate novel architectural concepts and heterogeneity at both the node and the system level to achieve power and performance goals. These future systems present new challenges and opportunities in how we approach computing.
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February 6, 2023 ececosem

Some Recent Combinatorial Algorithms in Tournament Scheduling and Secret Sharing

For tournament scheduling, we consider scheduling of round robin home – away tournament where each team plays at most k consecutive home/away games. The
hardness of this problem is discussed and some results for k = 2, 3 and greater than 3
are presented as separate cases.
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January 11, 2023 ececosem

Gradual Verification: Assuring Programs Incrementally

While software is becoming more ubiquitous in our everyday lives, so are unintended bugs. In response, static verification techniques were introduced to prove or disprove the absence of bugs in code. Unfortunately, current techniques burden users by requiring them to write inductively complete specifications involving many extraneous details. To overcome this limitation, I introduce the idea of gradual verification, which handles complete, partial, or missing specifications by soundly combining static and dynamic checking. As a result, gradual verification allows users to specify and verify only the properties and components of their system that they care about and increase the scope of verification gradually—which is poorly supported by existing tools.
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November 29, 2022 ececosem

Bootstrapping Library-Based Synthesis

Constraint-based program synthesis techniques have been widely used in numerous settings. However, synthesizing programs that use libraries remains a major challenge. To handle complex or black-box libraries, the state of the art is to provide carefully crafted mocks or models to the synthesizer, requiring extra manual work. We address this challenge by proposing Toshokan, a new synthesis framework as an alternative approach in which library-using programs can be generated without any user-provided artifacts at the cost of moderate performance overhead.
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November 1, 2022 Fall 2022

Challenges in Engineering Secure Software Systems

Software security is a growing concern leading to the increasing adoption of a secure by design approach to software development. In such approach, software systems are designed from the ground up to be resilient against attacks. Despite the growing efforts into addressing security concerns early on during software development, mistakes can be made that lead to vulnerabilities (“software weaknesses*).

October 4, 2022 Fall 2022

A Framework for Feedback Guided Generation of Binaries

Binary analysis is an important capability required for many security and software engineering applications. Consequently, there are many binary analysis techniques and tools with varied capabilities. However, testing these tools requires a large, varied binary dataset with corresponding source-level information. In this paper, we present Cornucopia, an architecture agnostic automated framework that can generate a plethora of binaries from corresponding program source by exploiting compiler optimizations and feedback-guided learning.

September 27, 2022 Fall 2022

SIMR: Single Instruction Multiple Request Processing for Energy-Efficient Data Center Microservices

Contemporary data center servers process thousands of similar, independent requests per minute. In the interest of programmer productivity and ease of scaling, workloads in data centers have shifted from single monolithic processes toward a micro and nanoservice software architecture. As a result, single servers are now packed with many threads executing the same, relatively small task on different data.