arXiv subjects

Xuan Zeng

Publications and source records attributed to Xuan Zeng.

21 records · Page 2Linked to original sources

arXiv2016

MAP-Me: Managing Anchor-less Producer Mobility in Information-Centric Networks

Mobility has become a basic premise of network communications, thereby requiring a native integration into 5G networks. Despite the numerous efforts to propose and to standardize effective mobility management models for IP, the result is a complex, poorly flexible set of mechanisms. The natural support for mobility offered by ICN (Information Centric Networking), makes it a good candidate to define a radically new solution relieving limitations of traditional approaches. If consumer mobility is supported in ICN by design, in virtue of its connectionless pull-based communication model, producer mobility is still an open challenge. In this work, we propose MAP-Me, an anchor-less solution to manage micro mobility of content producer via ICN name-based data plane, with support for latency-sensitive applications. First, we analyze MAP-Me performance and provide guarantees of correctness and stability. Further, we set up a realistic simulation environment in NDNSim 2.1 for MAP-Me evaluation and comparison against existing solutions: either random waypoint and trace-driven car mobility patterns are considered under 802.11 radio access. Results are encouraging and highlight the superiority of MAP-Me in terms of user performance and of network cost metrics.

cs.NI↗

arXiv2016

A Memristor Crossbar-Based Computation Scheme with High Precision

The memristor is promising to be the basic cell of next-generation computation systems. Compared to the traditional MOSFET device, the memristor is efficient over energy and area. But one of the biggest challenges faced with researchers is how to program a memristor's resistance precisely. Recently, an algorithm designed to save 8 valid bits in each memristor is proposed, but this is still not sufficient for precise computation. In this paper, we propose a crossbar-based memristor computation scheme supporting precise computations whose operands have 32 valid bits. As a brief introduction, in a multiplication with two operands, one operand is programmed as input signal, and the other operand is saved into a so-called crossbar structure, which contains a group of memristors, and each memristor saves several valid bits, usually one or two bits only. The computation results,i.e. the multiplication of the two operands, are contained in the outputs of the crossbar structure together with noise. Analog-to-Digital Converters (ADCs) are then used to extract the valid bits, which are the most significant bits of outputs. These valid bits can be combined together with Digital-to-Analog Converters(DACs) to get the final results. What's more, the precision of this computation scheme can be adjusted according to the definition of the user, 32 valid bits at most, so it is qualified for different application contexts.

cs.ET↗

arXiv2013

A parallel method for solving Laplace equations with Dirichlet data using local boundary integral equations and random walks

In this paper, we will present a new approach for solving Laplace equations in general 3-D domains. The approach is based on a local computation method for the DtN mapping of the Laplace equation by combining a deterministic (local) boundary integral equation method and the probabilistic Feynman-Kac formula of PDE solutions. This hybridization produces a parallel algorithm where the bulk of the computation has no need for data communications. Given the Dirichlet data of the solution on a domain boundary, a local boundary integral equation (BIE) will be established over the boundary of a local region formed by a hemisphere superimposed on the domain boundary. By using a homogeneous Dirichlet Green's function for the whole sphere, the resulting BIE will involve only Dirichlet data (solution value) over the hemisphere surface, but over the patch of the domain boundary intersected by the hemisphere, both Dirichlet and Neumann data will be used. Then, firstly, the solution value on the hemisphere surface is computed by the Feynman-Kac formula, which will be implemented by a Monte Carlo walk on spheres (WOS) algorithm. Secondly, a boundary collocation method is applied to solve the integral equation on the aforementioned local patch of the domain boundary to yield the required Neumann data there. As a result, a local method of finding the DtN mapping is obtained, which can be used to find all the Neumann data on the whole domain boundary in a parallel manner. Finally, the potential solution in the whole space can be computed by an integral representation using both the Dirichlet and Neumann data over the domain boundary.

math.NA↗