We describe two token-based methods for authentication within Facebook to provide secure authorization within Facebook's infrastructure.

Joint work with Callen Rain, Stephen Weis, Yueting Lee, Haozhi Xiong, and Benjamin Yang.

We initiate a systematic study of mmap-based constructions, building a general framework, called 5Gen, to experiment with program obfuscation and multi-input functional encryption.

Joint work with Alex Malozemoff, Daniel Apon, Brent Carmer, Adam Foltzer, Daniel Wagner, David Archer, Dan Boneh, Jonathan Katz, and Mariana Raykova.

We give new constructions of order-revealing encryption with improved security guarantees and also show how to perform range queries efficiently in a manner that is robust against inference attacks.

Joint work with David J. Wu.

We construct inner product encryption with the function-hiding property, and we validate the practicality of our encryption scheme through implementation.

Joint work with Sam Kim, Avradip Mandal, Hart Montgomery, Arnab Roy, and David J. Wu.

We show how to construct an order-revealing encryption scheme which is not only more secure than all other existing order-preserving encryption schemes, but is also practical.

Joint work with Nathan Chenette, Stephen A. Weis, and David J. Wu.

We introduce the notion of key privacy for a constrained PRF, which captures the intuition that an adversary, given two constrained keys, cannot distinguish their constraints.

Joint work with Dan Boneh and David J. Wu.

We show how to construct the first implementable functional encryption scheme on multiple inputs using multilinear maps.

Joint work with Dan Boneh, Mariana Raykova, Amit Sahai, Mark Zhandry, and Joe Zimmerman.

We present a new way to encode weighted sums into unweighted pairwise constraints, with implications to the k-SUM problem, and also with finding cliques in node-weighted graphs.

Joint work with Amir Abboud and Ryan Williams.

We show how to construct pseudorandom functions that are secure against a large class of related-key attacks.

Joint work with Hart Montgomery and Ananth Raghunathan.

We construct the first provably secure key homomorphic pseudorandom functions in the standard model.

Joint work with Dan Boneh, Hart Montgomery, and Ananth Raghunathan.

We connect natural subgraph finding problems on edge-weighted graphs with the infamous k-Sum Conjecture, establishing tight reductions between graph problems and decision problems on sums.

Joint work with Amir Abboud.

We consider a model of user engagement in social networks, where each player incurs a cost to remain engaged but derives a benefit proportional to the number of engaged neighbors.

Joint work with Kshipra Bhawalkar, Jon Kleinberg, Tim Roughgarden, and Aneesh Sharma.

We analyze the online version of the min-cost metric matching problem on k servers and k requests, and show how a simple randomized algorithm obtains an O(log k)-competitive solution on the line metric.

Joint work with Anupam Gupta.

We study iterated transductions defined by a class of invertible transducers over the binary alphabet.

Joint work with Klaus Sutner.