Communication complexity

About: Communication complexity is a research topic. Over the lifetime, 3870 publications have been published within this topic receiving 105832 citations.

Method to design network-on-chip (noc)-based communication systems

Abstract: To tackle the increasing communication complexity of multi-core systems, scalable Networks on Chips (NoCs) are needed to interconnect the processor, memory and hardware cores of the systems. For the use of NoCs to be feasible in today's industrial designs, a custom-tailored, application-specific architecture that satisfies the objectives and constraints of the targeted application domain is required. In this work we present a method for synthesizing such application-specific NoC architectures. This best topology is achieved by a method to design Networks on Chips (NoCs)-based communication system for connecting on-chip components in a multicore system, said system comprising several elements such as processors, hardware blocks, memories, communicating through the communication system, said communication system comprising at least switches, said method comprising the steps of: - obtaining predefined communication characteristics modelling the applications running on the multicore system, - establishing the number and configuration of switches to connect the elements, - establishing physical connectivity between the elements and the switches, - for each of at least two pairs of communicating elements : a defining a communication path, that is, a sequence of switches to be traversed to connect the aforementioned pair of communicating elements, b calculating metrics as affected by the need to render said path into physical connectivity, said metrics being selected among one or a combination of power consumption of the involved switches, area of the involved switches, number of inputs and outputs of the involved switches, total length of wires used, maximum possible speed of operation of the system and number of switches to be traversed, taking into account any previously defined physical connectivity, c iterating the steps a and b for a plurality of possible paths, d choosing the path having the optimal metrics, e establishing any missing physical connectivity between the switches so that the selected optimal path occurs across physically connected switches.

Indoor Localization with Low Complexity in Wireless Sensor Networks

Abstract: Autonomous localization of nodes in wireless sensor networks is essential to minimize the complex self organization task consequently enhancing the overall network lifetime. Recently, precise indoor localization is impeded by multi path propagation of signals due to reflections at walls or objects. In this paper we partly overcome some of these problems by methods like frequency diversity and averaging multiple measured data. Received radio signal strength (RSS) in combination with weighted centroid localization, featuring low communication overhead and a low complexity of O(n), is our basis of a localization on the energy constrained sensor nodes. We first analyze the RSS-characteristics on a specific sensor node platform in different rooms. Next, we describe methods to improve these characteristics to reach best localization results at minimized complexity. Finally, in a practice indoor localization we achieve a small localization error of only 14% for 69% of all test-points that was enhanced to at least 8% in average by simple optimizations. For that, no hardware modifications as well as time consuming RSSI-maps or complex signal propagation models are required.

Chinese remainder theorem based centralised group key management for secure multicast communication

Abstract: Designing a centralised group key management with minimal computation complexity to support dynamic secure multicast communication is a challenging issue in secure multimedia multicast. In this study, the authors propose a Chinese remainder theorem-based group key management scheme that drastically reduces computation complexity of the key server. The computation complexity of key server is reduced to O (1) in this proposed algorithm. Moreover, the computation complexity of group member is also minimised by performing one modulo division operation when a user join or leave operation is performed in a multicast group. The proposed algorithm has been implemented and tested using a key-star-based key management scheme and has been observed that this proposed algorithm reduces the computation complexity significantly.

Communication complexity and combinatorial lattice theory

Abstract: In a recent paper, Hajnal, Maass, and Turan analyzed the communication complexity of graph connectivity. Building on this work, we develop a general framework for the study of a broad class of communication problems which has several interesting special cases including the graph connectivity problem. The approach is based on the combinatorial theory of alignments and lattices.