Victor Zakhary

Victor Zakhary

Research Assistant - Computer Science - UCSB

About Me

I am a research assistant and a PhD candidate at the Distributed Systems Lab (DSL) at UCSB. I am interested in blockchains, distributed systems, data privacy and security, and privacy of social network users. My current research focuses on scaling and extending the functionality of permissionless blockchains. I currently work on a protocol to support atomic cross-chain transaction. Also, I work on adding transactional support to smart contracts. These protocols are steps towards building a global asset management system on permissionless blockchain infrastructures. In addition, I work on developing client-side caching protocols to resolve server-side load-imbalance in large scale distributed caching systems. Finally, I work on solving the fault-tolerance problem of ORAM stores, in addition to building client-centric tools to preserve the privacy of social network users.

Papers

Victor Zakhary, Divy Agrawal, Amr El Abbadi "Atomic Commitment Across Blockchains" preprint [pdf]

Victor Zakhary, Ishani Gupta, Rey Tang, Amr El Abbadi "Multifaceted Privacy: How to Express Your Online Persona without Revealing Your Sensitive Attributes" preprint [pdf]

Victor Zakhary, Mohammad Javad Amiri, Sujaya Maiyya, Divyakant Agrawal, Amr El Abbadi "Towards Global Asset Management in Blockchain Systems" BCDL co-located with VLDB 2019 [pdf]

Sujaya Maiyya, Victor Zakhary, Divy Agrawal, Amr El Abbadi "Database and Distributed Computing Foundations of Blockchains" SIGMOD 2019 (tutorial) [pdf] [slides].

Sujaya Maiyya, Victor Zakhary, Divy Agrawal, Amr El Abbadi "Database and Distributed Computing Fundamentals for Scalable, Fault-tolerant, and Consistent Maintenance of Blockchains" VLDB 2018 (tutorial) [pdf] [slides].

Victor Zakhary, Cetin Sahin, Amr El Abbadi, Huijia (Rachel) Lin, and Stefano Tessaro. "Pharos: Privacy Hazards of Replicating ORAM Stores" EDBT 2018 ( Best Demonstration Award) [pdf].

Victor Zakhary, Faisal Nawab, Divy Agrawal, Amr El Abbadi "Global-Scale Placement of Transactional Data Stores" EDBT 2018 [pdf]

Faisal Nawab, Vaibhav Arora, Victor Zakhary, Divy Agrawal, Amr El Abbadi "A System Infrastructure for Strongly Consistent Transactions on Globally-Replicated Data." IEEE Data Engineering Bulletin 2017 [pdf]

Victor Zakhary, Cetin Sahin, Theodore Georgiou, Amr El Abbadi "LocBorg: Hiding Social Media User Location while Maintaining Online Persona" SIGSPATIAL 2017 (Second Place Best Vision Paper Award) [pdf]

Victor Zakhary, Divy Agrawal, Amr El Abbadi "Caching at the Web Scale" VLDB 2017 (tutorial) [pdf] [pptx].

Victor Zakhary, Divy Agrawal, Amr El Abbadi "Caching at the Web Scale" WWW 2017 (tutorial) [pdf] [pptx].

Cetin Sahin, Aaron Magat, Victor Zakhary, Amr El Abbadi, Huijia (Rachel) Lin, and Stefano Tessaro. "Understanding the Security Challenges of Oblivious Cloud Storage with Asynchronous Accesses" ICDE 2017 (Demo) [pdf] [video]

Victor Zakhary, Faisal Nawab, Divy Agrawal, Amr El Abbadi. "DB-Risk: The Game of Global Database Placement" SIDMOD 2016 (Demo) [pdf] [online demo].

Cetin Sahin, Victor Zakhary, Amr El Abbadi, Huijia (Rachel) Lin, and Stefano Tessaro. "TaoStore: Overcoming Asynchronicity in Oblivious Data Storage" S&P 2016. [pdf].

Victor Zakhary, Hicham G. Elmongui, and Magdy H. Nagi. "MobiPLACE*: A Distributed Framework for Spatio-Temporal Data Streams Processing Utilizing Mobile Clients’ Processing Power." Mobiquitous 2013 [pdf].

Teaching Experience

I served as the Lead TA in the Computer Science department at UCSB 2015-2016. I worked as a teaching assistant for 6+ years(2010-2017). At UCSB(2013-2017), I assisted teaching the following classes at UCSB:

  • CS130A: Data Structures and Algorithms using C++ - Winter 2016
  • CS501: Pedagogies and Teaching Strategies for the new graduate students - Fall 2015
  • CS171: Distributed Systems - Spring 2015, Spring 2017
  • CS40: Computer Foundation and Discrete Mathematics - Winter 2015
  • CS271: Distributed Systems, graduate class - Fall 2014
  • CS138: Automata and Languages - Spring 2014
  • CS130A: Data Structures and Algorithms using C++ - Winter 2014
  • CS8: Introduction to Programming using Python - Fall 2013, Spring 2016

In addition, I worked as a Teaching assistant for three years (2010-2013) at the department of Computer and Systems Engineering in Alexandria University, Egypt. I assisted teaching the following classes:

  • Introduction to Programming using Python
  • Introduction to Programming using QBasic
  • Computer Architecture
  • Microprocessors
  • Discrete Mathematics and its Applications
  • Linear Control Systems
  • Data Structures using C++

Awards

  • The Outstanding Teaching Assistant from the Computer Science Department at UCSB for the academic year 2018-19
  • Best Demonstration Award in EDBT 2018 news
  • Second Place Best Vision Paper Award in SIGSPATIAL 2017 news
  • The Outstanding Teaching Assistant in the Computer Science Program from the College of Engineering at UCSB for the academic year 2016-17
  • Nominated to the campus-wide Outstanding Teaching Assistant Award 2016-17
  • Doctoral Student Travel Grant 2016-17
  • Oracle Reseach fellowship 2016-17
  • The Outstanding Teaching Assistant from the Computer Science Department at UCSB for the academic year 2015-16
  • The Outstanding Teaching Assistant in the Computer Engineering Program from the College of Engineering at UCSB for the academic year 2014-15
  • The Distinguished Teaching Assistant from the Computer Science Department at UCSB for the academic year 2014-15

Leadership Experience

  • CS Graduate affairs committee member (2015-2016)
  • CS lead teaching assistant (2015-2016)

Industrial Work Experience

PhD Software Engineer Intern - Ads Integrity (Ragnarok) - Google (June 2017 - September 2017)

I built host features data collection, aggregation, and cleaning pipelines. Then I used a clustering system at Google to cluster advertisement hosts to catch hosts that share features with malicious hosts and block the ones that are malicious (ِA malicious ad host might be sending malware or doing cloaking in ads).

PhD Software Engineer Intern - Ads Infrastructure - Google (June 2016 - September 2016)

I worked on resource optimization and dynamic load balancing for a very large scale caching layer to support hundreds of millions of keys lookups per second. By the end of the internship, I helped saving 40% of the server cpu usage for this caching service.

PhD Software Engineer Intern- Vanadium - Google (June 2015 - September 2015)

I built a distributed p2p file system over a distributed p2p key/value store. We built a POSIX like api to support file and directory hierarchy management. In addition, we support sharing between multiple clients enforcing the file system's permissions semantics.

Software Engineer Intern at Sears Holdings Corporation (June 2014 - September 2014)

I worked in the search optimization team. Throughout my internship, I built services and debugging tools to provide the team better understanding about their core search responses. Also, we developed a proof of concept solving similar product problem based on product's features. We used typical tf-idf text similarity technique. We also updated the similarity scores using topics generated by LDA topic modelling algorithm to get better short text similarity scores.

Co-founder of Kdev (Kreation development), Alexandria, Egypt (February 2012 – August 2013)

I helped cofounding Kreation development IT solutions in Alexandria, Egypt. I also worked as web and mobile freelancer developer on Odesk(Upwork).

Software Engineer in Innuva IT solutions, Alexandria, Egypt (February 2011 – February 2012)

Solved performance and scalability problems of web applications by distributing computation load between client and server and reduce communication load by caching.