Thanks to the improvements experienced in technology in the last few years, most especially in virtual reality systems, the number and potential of networked virtual environments or NVEs and their users are increasing. NVEs aim to give distributed users a feeling of immersion in a virtual world and the possibility of interacting with other users or with virtual objects inside it, like when they interact in the real world. Being able to provide that feeling and natural interactions when the users are geographically separated is one of the goals of these systems. Nevertheless, this goal is especially sensitive to different issues, such as different connections with heterogeneous throughput or different network latencies, which can lead to consistency and synchronization problems and, thus, to a worsening of the users' quality of experience or QoE. With the purpose of solving these issues, researchers have proposed and evaluated numerous technical solutions, in fields like network architectures, data distribution and filtering, resource balancing, computing models, predictive modeling and synchronization in NVEs. This paper gathers and classifies them, summarizing their advantages and disadvantages, using a new way of classification. With the current increase of the number of NVEs and the multiple solutions proposed so far, this work aims to become a useful tool and a starting point not only for future researchers in this field but also for those who are new in NVEs development, in which guaranteeing a good users' QoE is essential.
翻译:由于在过去几年里在技术方面,特别是在虚拟现实系统方面经历的改进,网络虚拟环境或NVE及其用户的数量和潜力正在增加。NVE的目的是让分布式用户感到在虚拟世界中沉浸,并有可能与其他用户或虚拟对象在虚拟世界中进行互动,例如他们在现实世界中互动。当用户在地理上隔开时,能够提供这种感觉和自然互动是这些系统的目标之一。然而,这个目标特别敏感于不同的问题,例如与多样化的吞吐量或不同的网络晚期的不同连接,这可能导致一致性和同步问题,从而导致用户经验或QoE质量的恶化。为了解决这些问题,研究人员在网络结构、数据分发和过滤、资源平衡、计算模型、预测模型和NVE中同步等领域提出和评价了许多技术解决方案。这份文件收集并分类了这些解决方案,用新的分类方法总结了它们的利弊。随着目前NVE数量增加,用户的经验质量或QE质量恶化,从而导致用户的经验质量或QE质量的恶化。为了解决这些问题,研究人员们已经提出和评价了许多技术解决方案,在网络结构、数据、数据分配、计算模型、预测模型和同步化模型和同步化方面,这些工具对于研究人员来说也只是一个有用的工具。