We discuss relationships between client-centric consistency models (known as session guarantees), and data-centric models. The first group includes: read-your-writes guarantee, monotonic-writes monotonic-reads guarantee writes-follow-reads guarantee. other atomic consistency, sequential causal processor PRAM weak release scope entry consistency. use a consistent notation to present formal definitions of both kinds in the context replicated shared objects. Next, we prove relationship model...

Matchmaking players is an important problem in online multiplayer games. Existing solutions employ client-server architecture, which induces several problems. Those range from additional costs associated with infrastructure maintenance to inability play the game once servers become unavailabe (due being under Denial of Service attack or shut down after earning enough profit). This paper aims provide a solution for matchmaking on scale Internet, without using central server. In order achieve...

This paper deals with the problem of store-and-forward deadlock prevention in networks. The presented solution uses time stamping all messages network, and a nonpreemptable message exchange mechanism. By combining these ideas, new distributed flow control procedure is derived which guarantees that are delivered to their own destinations, thus avoiding both livelock without any loss. It shown some properties this depend on policy allocation buffers nodes. On one hand, an optimal strategy...

In this paper we tackle the issue of exchanging and integrating medical information originating from different health care systems. We propose a solution - Healthcare Integration Platform (HIP) which utilises some concepts contained in IHE profiles combined with existing EHR standards order to maintain high level interoperability. confirm value our by presenting working prototype based on concepts. The relies Service Oriented Architecture paradigm using RESTful web services.

Backward error recovery is one of the most used schemes to ensure fault-tolerance in distributed systems. It consists, upon occurrence a failure, restoring computation an error-free global state from which it can be resumed produce correct behaviour. Checkpointing techniques pursue backward recovery. As we consider large-scale systems, on side coordinated approach take checkpoints not practicable, other for uncoordinated probability have domino effect during could no longer negligible. In...

Composition of Web Services (WS) into business processes (BP) often results in occurrence defects a process: implicit dependencies, incorrect contexts, non-optimal or bottlenecked workflow, and deadlocks. To deal with these problems, WS Mining (process mining SOA) research provides methods tools to discover, evaluate enhance real world basing on process model discovered from log. Unfortunately, current this field only concerns SOAP-WS which are not as well-suited RESTful-WS the context...

Abstract Currently existing solutions rarely protect message integrity, authenticity and user anonymity without burdening the with details of key management. To address this problem, we present Aldeon-a protocol for anonymous group conversations in a peer-to-peer system. The efficiency Aldeon is based on novel tree synchronization algorithm, which proposed discussed paper. By using significant reduction number exchanged messages achieved. In paper, formal definition hash branch function...

The proliferation of web services and the wide choice Web technologies has resulted in increasing use browsers by service-oriented applications. To decrease overloading websites thus make them more attractive for SOA applications, various solutions to deliver content resources through are considered. Among existing approaches, WebRTC is used P2P delivery networks. In this paper we conduct their comprehensive evaluation, compare performance multiple real-world cases determine practical...

In communicating resource systems (CRS), a set of independent, hierarchically composed resources communicate to realize business process. Examples CRSs include RESTful Web services, cloud computing platforms and hierarchical distributed systems. Unfortunately, their complexity, nature, usually long lifespan can lead problems like livelocks, deadlock occurrences invocation loops. This makes hard maintain manage; it also leads loss QoS or system failures. Moreover, is important take into...

A problem of deadlock avoidance in store-and-forward networks with at least two buffers per node is considered for fixed as well dynamic routing. For both cases polynomial time, centralized algorithms are proposed and shown to be optimal a sense possible buffer utilization. When the number equal one each known NP-complete, thus, unlikely admit polynomial-time algorithm. The presented results may also interesting other applications, some massively parallel computer systems being examples.<...