Survey on the Event Orderings Semantics Used for Distributed System

Abstract

Abstract-Event ordering in distributed system (DS) is disputable and proactive subject in DS particularly with the emergence of multimedia synchronization. According to the literature, different type of event ordering is used for different DS mode such as asynchronous or synchronous. Recently, there are several novel implementation of these types introduced to fulfill the demand for establishing a certain order according to a specific criterion in DS with lighter complexity. Purpose -This paper demonstrates most significant implementation of types of event ordering in DS. Designing, methodology, approach -This paper firstly, present each type separately. Then it presents its implementation approaches. The comparison between those types is achieved later in the paper. Finding -Most types used in event ordering in DS share same properties with some delicate differences. However, some types which used for asynchronous mode cannot be used in the synchronous. Value -This paper is considered as a reference for scholars how desire to direct their research; develop potential investigation; or introduce new type of event orderings in DS. Keywords-component;Distributed system; event ordering; INTRODUCTIONA distributed system refers to a system that consists of a number of computers that do not share a memory or a clock and communicate with each other by exchanging messages over a communication network. A distributed operating system operates on multiple autonomous computers but appears to its users as a single machine. Figure ( Obviously, there are several benefits from using such system. Performance is improved and the cost is reduced with the exception of certain special computation intensive applications, equivalent computing power may be obtained with a network of workstations at a much lower cost than a traditional time-sharing system. Requests of services may be satisfied using hardware/software resources on other computers on the communication network which means an enormous increase in resource sharing [4]. Furthermore, concurrent execution of tasks and load distributing can lead to improved response time. Moreover, fault tolerance can be achieved through the replication of data and services. Finally, one distinct feature is new hardware and software resources can be added without replacing the existing resources which called as modular expandability [8].On the other hand, there are several drawbacks of using distributed system as highlighted next. The global knowledge problem which means that global state of the system is hard to acquire due to the unavailability of a global memory and a global clock and the unpredictability of message delays [10]. Naming is another problem which means the directory of all the named objects in the system (services, files, users, printers, etc.) must be maintained to allow proper access. Both schemes of replicated directories and partitioned directories have their strengths and weaknesses. Scalability which defined as any mechanisms or approaches adopted in a system must not resul...