Jonathan Z. Sun

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We study the problem of broadcasting confidential information to a collection of n devices while providing the ability to revoke an arbitrary subset of those devices (and tolerating collusion among the revoked devices). In this paper, we restrict our attention to low-memory devices, that is, devices that can store at most O(log n) keys. We consider(More)
We present a new multi-dimensional data structure, which we call the skip quadtree (for point data in R<sup>2</sup>) or the skip octree (for point data in R<sup>d</sup>, with constant d &gt; 2). Our data structure combines the best features of two well-known data structures, in that it has the well-defined "box"-shaped regions of region quadtrees and the(More)
We present a distributed data structure, which we call the <i>rainbow skip graph</i>. To our knowledge, this is the first peer-to-peer data structure that simultaneously achieves high fault-tolerance, constant-sized nodes, and fast update and query times for ordered data. It is a non-trivial adaptation of the SkipNet/skip-graph structures of Harvey <i>et(More)
Geometric greedy routing uses (virtual) geographic point locations as addresses for the purposes of routing, while routing decisions are made by each node individually based only on local information. It requires that the network topology is greedily embedded in a metric space through assigning virtual coordinates to the nodes in the network. Recent(More)
We present a distributed data structure, which we call the rainbow skip graph. To our knowledge, this is the first peer-to-peer data structure that simultaneously achieves high faulttolerance, constant-sized nodes, and fast update and query times for ordered data. It is a non-trivial adaptation of the SkipNet/skip-graph structures of Harvey et al. and(More)
A clustered graph has its vertices grouped into clusters in a hierarchical way via subset inclusion, thereby imposing a tree structure on the clustering relationship. The c-planarity problem is to determine if such a graph can be drawn in a planar way, with clusters drawn as nested regions and with each edge (drawn as a curve between vertex points) crossing(More)
The transfer of spin angular momentum from a spin-polarized current to a ferromagnet can generate sufficient torque to reorient the magnet’s moment. This torque could enable the development of efficient electrically actuated magnetic memories and nanoscale microwave oscillators. Yet difficulties in making quantitative measurements of the spin-torque vector(More)