Ahmed Kosba

I am an assistant professor at the Computer and Systems Engineering Department at the Faculty of Engineering at Alexandria University. My research interests are in the broad areas of security and applied cryptography, with a focus on privacy-preserving techniques (such as zero-knowledge proofs) and the intersection of machine learning and security.
Since 2023, I also work as an R&D leader at MCIT's Applied Innovation Center, addressing problems of national interest, mainly fraud detection.

Previously, I was a postdoctoral scholar at UC Berkeley, hosted by Prof. Dawn Song. In 2018, I received my PhD degree from the Computer Science Department at the University of Maryland, where I was a research assistant at the Maryland Cybersecurity Center (MC2) working on zero-knowledge proofs and blockchains. My PhD advisors were Prof. Elaine Shi and Prof. Charalampos Papamanthou.

[Github] [Google Scholar]

Contact: ahmed.kosba AT alexu.edu.eg

Publications

Conference and Journal Publications

MIRAGE: Succinct Arguments for Randomized Algorithms with Applications to Universal zk-SNARKs
Ahmed Kosba, Dimitrios Papadopoulos, Charalampos Papamanthou, and Dawn Song
USENIX Security 2020.
[PDF] [Code]
xJsnark: A Framework for Efficient Verifiable Computation
Ahmed Kosba, Charalampos Papamanthou, Elaine Shi
IEEE Symposium on Security and Privacy, 2018.
[PDF] [Code]
Solidus: Confidential Distributed Ledger Transactions via PVORM
Ethan Cecchetti, Fan Zhang, Yan Ji, Ahmed Kosba, Ari Juels, Elaine Shi
ACM Conference on Computer and Communications Security (CCS), 2017.
[PDF]
The Ring of Gyges: Investigating the Future of Criminal Smart Contracts
Ari Juels, Ahmed Kosba, Elaine Shi
ACM Conference on Computer and Communications Security (CCS), 2016.
[PDF] [Video] [Media: MIT Technology Review]
Hawk: The Blockchain Model of Cryptography and Privacy-Preserving Smart Contracts
Ahmed Kosba, Andrew Miller, Elaine Shi, Zikai Wen, Charalampos Papamanthou.
IEEE Symposium on Security and Privacy, 2016.
[PDF]
On Scaling Decentralized Blockchains (A Position Paper)
Kyle Croman, Christian Decker, Ittay Eyal, Adem Efe Gencer, Ari Juels, Ahmed Kosba, Andrew Miller, Prateek Saxena, Elaine Shi, Emin Gun Sirer, Dawn Song, Roger Wattenhofer.
The 3rd Workshop on Bitcoin and Blockchain Research, 2016.
[PDF] [Media: MIT Technology Review]
Step by Step Towards Creating a Safe Smart Contract: Lessons and Insights from a Cryptocurrency Lab
Kevin Delmolino, Mitchell Arnett, Ahmed Kosba, Andrew Miller, and Elaine Shi
The 3rd Workshop on Bitcoin and Blockchain Research, 2016.
[PDF] [Website]
Non-outsourceable Scratch-Off Puzzles to Discourage Bitcoin Mining Coalitions
Andrew Miller, Elaine Shi, Ahmed Kosba, Jonathan Katz
ACM Conference on Computer and Communications Security (CCS), 2015. [PDF]
TRUESET: Faster Verifiable Set Computations
Ahmed Kosba, Dimitrios Papadopoulos, Charalampos Papamanthou, Mahmoud F. Sayed, Elaine Shi, Nikos Triandopoulos
USENIX Security 2014. [PDF]
Ichnaea: A Low-Overhead Robust WLAN Device-Free Passive Localization System
Ahmed Saeed, Ahmed Kosba, Moustafa Youssef
IEEE Journal of Selected Topics in Signal Processing, 2014. [PDF]
Nuzzer: A Large-Scale Device-Free Passive Localization System for Wireless Environments
Moustafa Seifeldin, Ahmed Saeed, Ahmed Kosba, Amr El-Keyi, Moustafa Youssef
IEEE Transactions of Mobile Computing, 2013. [PDF]
ReVISE: An RF-based Vehicle Detection and Speed Estimation System
Nehal Kassem, Ahmed Kosba, Moustafa Youssef
IEEE 75th Vehicular Technology Conference, 2012.
RASID: A Robust WLAN Device-free Passive Motion Detection System
Ahmed Kosba, Ahmed Saeed, Moustafa Youssef
IEEE Pervasive Computing and Communication (PerCom) Conference, 2012. [PDF]
Analysis of a Device-free Passive Tracking System in Typical Wireless Environments
Ahmed Kosba, Ahmed Abdelkader, Moustafa Youssef
IFIP 3rd International Conference on New Technologies, Mobility and Security (NTMS), 2009. (Undergraduate Project) [PDF]

Posters/Demos

ADAM: Automated Detection and Attribution of Malicious Webpages
Ahmed Kosba, Aziz Mohaisen, Andrew West, Trevor Tonn
(Poster) IEEE CNS, 2013.
RASID Demo: A Robust WLAN Device-free Passive Motion Detection System
Ahmed Kosba, Moustafa Youssef
(Demo) IEEE Pervasive Computing and Communication (PerCom) Conference, 2012. [Video]
A Robust Technique for WLAN Device-free Passive Motion Detection
Ahmed Kosba, Ahmed Saeed, Moustafa Youssef
(Poster) MobiCom, 2011.

Preprints

How to use SNARKs in Universally Composable Protocols
Ahmed Kosba, Zhichao Zhao, Andrew Miller, Yi Qian, Hubert Chan, Charalampos Papamanthou, Rafael Pass, abhi shelat, Elaine Shi.
Online Preprint. [PDF]

Education

Ph.D., Computer Science, University of Maryland, College Park [2012 - 2018]
M.Sc., Faculty of Engineering, Alexandria University, Egypt [2009 - 2012]
B.Sc. Faculty of Engineering, Alexandria University, Egypt [2005 -2009]

Teaching

Faculty of Engineering, Alexandria University:
- CC551/CSE468: Computer and Network Security (Spring'20, Fall'22, Spring'23, Fall'23, Fall'24, Fall'25)
- CSE762: Privacy-preserving Data Analysis and Machine Learning (Spring'25)
- CC552/CSE469: Distributed Systems (Spring'24, Spring'25)
- CSE492/CC491: Blockchains, Cryptocurrencies and Smart Contracts (Fall'20, Fall'21, Fall'22, Spring'23, Fall'23, Fall'24, Fall'25)
- CSE321/CC371: Analysis and Design of Algorithms (Fall'19, Fall'21, Spring'22, Fall'22, Fall'23, Fall'24, Fall'25)
- HS444: Social Risks and Security of Computer Systems (Spring'20, Spring'21, Spring'22)
- CSE343/CS334: Embedded Systems (Spring'20, Spring'21, Spring'22, Spring'23)
- CS331: Microprocessors Systems - Hardware Security Module (Fall'20)
- CSE131: Digital Logic Design (Fall'19)
UC Berkeley:
- CS294-151: Blockchain and CryptoEconomics (Fall'18)
University of Maryland (Teaching Assistant - Fall 2012 to Fall 2015):
- CMSC417: Computer Networks, CMSC131/CMSC132: Object Oriented Programming I/II
Faculty of Engineering, Alexandria University (Teaching Assistant - Fall 2009 to Spring 2012):
- Probability, Statistics, Computer Networks, Performance Evaluation and C Programming

Awards

Dean's Fellowship for outstanding graduate students, Department of Computer Science, University of Maryland, 2016.
Distinguished Teaching Assistant Award, University of Maryland, May 2014.
Best poster award, IEEE CNS 2013.
Dean's Fellowship, University of Maryland [2012-2013].
Third Place, ACM SIGMOBILE Graduate Student Research Competition, 2011.
Certificate of Honor - Faculty of Engineering, Alexandria University, Egypt [2005-2009].
Silver medal in the Egyptian Olympiad of Informatics (EOI), 2006.