Distributed algorithm

About: Distributed algorithm is a research topic. Over the lifetime, 20416 publications have been published within this topic receiving 548109 citations.

Modeling and validating distributed embedded real-time systems with VDM++

Abstract: The complexity of real-time embedded systems is increasing, for example due to the use of distributed architectures. An extension to the Vienna Development Method (VDM) is proposed to address the problem of deployment of software on distributed hardware. The limitations of the current notation are discussed and new language elements are introduced to overcome these deficiencies. The impact of these changes is illustrated by a case study. A constructive operational semantics is defined in VDM++ and validated using VDMTools. The associated abstract formal semantics, which is not specific to VDM, is presented in this paper. The proposed language extensions significantly reduce the modeling effort when describing distributed real-time systems in VDM++ and the revised semantics provides a basis for improved tool support.

Fair Algorithms for Maximal Link Activation in Multihop Radio Networks

Abstract: We present a distributed algorithm for obtaining a fair time slot allocation for link activation in a multihop radio network. We introduce the concept of maximal fairness in which the termination of a fair allocation algorithm is related to maximal reuse of the channel under a given fairness metric. The fairness metric can be freely interpreted as the expected link traffic load demands, link priorities, etc. Since respective demands for time slot allocation will not necessarily be equal, we define fairness in terms of the closeness of allocation to respective link demands while preserving the collision free property. The algorithm can be used in conjunction with existing link activation algorithms to provide a fairer and fuller utilization of the channel.

An architectural co-synthesis algorithm for distributed, embedded computing systems

Abstract: Many embedded computers are distributed systems, composed of several heterogeneous processors and communication links of varying speeds and topologies. This paper describes a new, heuristic algorithm which simultaneously synthesizes the hardware and software architectures of a distributed system to meet a performance goal and minimize cost. The hardware architecture of the synthesized system consists of a network of processors of multiple types and arbitrary communication topology; the software architecture consists of an allocation of processes to processors and a schedule for the processes. Most previous work in co-synthesis targets an architectural template, whereas this algorithm can synthesize a distributed system of arbitrary topology. The algorithm works from a technology database which describes the available processors, communication links, I/O devices, and implementations of processes on processors. Previous work had proposed solving this problem by integer linear programming (ILP); our algorithm is much faster than ILP and produces high-quality results.

Diffusion Least-Mean Squares Over Adaptive Networks

Abstract: Distributed adaptive algorithms are proposed to address the problem of estimation in distributed networks. We extend recent work by relying on static and adaptive diffusion strategies. The resulting adaptive networks are robust to node and link failures and present a substantial improvement over the non-cooperative case asserting that cooperation improves estimation performance. The distributed algorithms are peer-to-peer implementations suitable for networks with general topologies.