Asynchronous communication

About: Asynchronous communication is a research topic. Over the lifetime, 28159 publications have been published within this topic receiving 430451 citations.

Multistage detection in asynchronous code-division multiple-access communications

Abstract: A multiuser detection strategy for coherent demodulation in an asynchronous code-division multiple-access system is proposed and analyzed. The resulting detectors process the sufficient statistics by means of a multistage algorithm based on a scheme for annihilating successive multiple-access interference. An efficient real-time implementation of the multistage algorithm with a fixed decoding delay is obtained and shown to require a computational complexity per symbol which is linear in the number of users K. Hence, the multistage detector contrasts with the optimum demodulator, which is based on a dynamic programming algorithm, has a variable decoding delay, and has a software complexity per symbol that is exponential in K. An exact expression is obtained and used to compute the probability of error is obtained for the two-stage detector, showing that the two-stage receiver is particularly well suited for near-far situations, approaching performance of single-user communications as the interfering signals become stronger. The near-far problem is therefore alleviated. Significant performance gains over the conventional receiver are obtained even for relatively high-bandwidth-efficiency situations. >

Enterprise Integration Patterns: Designing, Building, and Deploying Messaging Solutions

Abstract: Would you like to use a consistent visual notation for drawing integration solutions? Look inside the front cover. Do you want to harness the power of asynchronous systems without getting caught in the pitfalls? See "Thinking Asynchronously" in the Introduction. Do you want to know which style of application integration is best for your purposes? See Chapter 2, Integration Styles. Do you want to learn techniques for processing messages concurrently? See Chapter 10, Competing Consumers and Message Dispatcher. Do you want to learn how you can track asynchronous messages as they flow across distributed systems? See Chapter 11, Message History and Message Store. Do you want to understand how a system designed using integration patterns can be implemented using Java Web services, .NET message queuing, and a TIBCO-based publish-subscribe architecture? See Chapter 9, Interlude: Composed Messaging.Utilizing years of practical experience, seasoned experts Gregor Hohpe and Bobby Woolf show how asynchronous messaging has proven to be the best strategy for enterprise integration success. However, building and deploying messaging solutions presents a number of problems for developers. Enterprise Integration Patterns provides an invaluable catalog of sixty-five patterns, with real-world solutions that demonstrate the formidable of messaging and help you to design effective messaging solutions for your enterprise.The authors also include examples covering a variety of different integration technologies, such as JMS, MSMQ, TIBCO ActiveEnterprise, Microsoft BizTalk, SOAP, and XSL. A case study describing a bond trading system illustrates the patterns in practice, and the book offers a look at emerging standards, as well as insights into what the future of enterprise integration might hold.This book provides a consistent vocabulary and visual notation framework to describe large-scale integration solutions across many technologies. It also explores in detail the advantages and limitations of asynchronous messaging architectures. The authors present practical advice on designing code that connects an application to a messaging system, and provide extensive information to help you determine when to send a message, how to route it to the proper destination, and how to monitor the health of a messaging system. If you want to know how to manage, monitor, and maintain a messaging system once it is in use, get this book. 0321200683B09122003

Distributed Asynchronous Deterministic and Stochastic Gradient Optimization Algorithms

Abstract: We present a model for asynchronous distributed computation and then proceed to analyze the convergence of natural asynchronous distributed versions of a large class of deterministic and stochastic gradient-like algorithms. We show that such algorithms retain the desirable convergence properties of their centralized counterparts, provided that the time between consecutive communications between processors plus communication delays are not too large.

Providing quality of service over a shared wireless link

Abstract: We propose an efficient way to support quality of service of multiple real-time data users sharing a wireless channel. We show how scheduling algorithms exploiting asynchronous variations of channel quality can be used to maximize the channel capacity (i.e., maximize the number of users that can be supported with the desired QoS).

Distributed Computing: Fundamentals, Simulations and Advanced Topics

Abstract: 1. Introduction.PART I: FUNDAMENTALS.2. Basic Algorithms in Message-Passing Systems.3. Leader Election in Rings.4. Mutual Exclusion in Shared Memory.5. Fault-Tolerant Consensus.6. Causality and Time.PART II: SIMULATIONS.7. A Formal Model for Simulations.8. Broadcast and Multicast.9. Distributed Shared Memory.10. Fault-Tolerant Simulations of Read/Write Objects.11. Simulating Synchrony.12. Improving the Fault Tolerance of Algorithms.13. Fault-Tolerant Clock Synchronization.PART III: ADVANCED TOPICS.14. Randomization.15. Wait-Free Simulations of Arbitrary Objects.16. Problems Solvable in Asynchronous Systems.17. Solving Consensus in Eventually Stable Systems.References.Index.