Dynamic Service Aggregation for Interactive Information Delivery

数字音频和视频作为在计算机和通信系统中被操纵的数据越来越普遍。当前基于网络的多点信息传递的资源分配机制本质上是静态的，不能支持每个参与者的交互性。点对点方法可以支持交互性，但在扩展到大量参与者时效率低下。目前，还没有技术证明能够根据需要在每个会话进行中重新协商和扩展服务参数，以适应不同的终端设备特性和网络拥塞。该提案通过定义可分解服务组来解决这个问题，这些服务组允许聚合交互性、终端特征和服务扩展级别。交互性意味着唯一服务组的可用性。提出了一种基于变化的交互性和会话需求动态地将元素重新分配给服务组的机制。这种机制将允许根据成本、可用资源或用户设备特性来调整服务质量，并将适应不断变化的网络负载。该方法将终端应用程序的特点和数据存储需求应用于数据扩展机制的设计。本研究的具体任务是：(1)形式化描述和聚合服务组的模型；(2)开发动态服务聚合协议；(3)确定应用需求到服务组和网络服务质量的映射；(4)建立支持多会话服务退化和扩展的网络访问机制；并使用已建立的多点应用程序和组播协议进行评估。

Digital audio and video are increasingly common as data that are manipulated in computer and communication systems. Current resource allocation mechanisms for network-based multipoint information delivery are static in nature and cannot support interactivity for each participant. Point-to-point approaches can support interactivity but are inefficient for scaling to a large number of participants. Currently, no techniques have demonstrated the ability to renegotiate and scale service parameters per session in progress as required to adapt to differing terminal equipment characteristics and network congestion. The proposal addresses this problem through the definition of decomposable service groups that permit aggregation of interactivity, terminal characteristics, and levels of service scaling. Interactivity implies the availability of a unique service group. A mechanism is proposed to dynamically reassign elements to service groups based on changing interactivity and session requirements. Such a mechanism will allow the adjustment of service quality based on cost, available resources, or user-equipment characteristics, and will adapt to changing network loading. The proposed approach applies the characteristics of end applications and data storage requirements to the design of a data scaling mechanism. Specific tasks of this research are to (1) formalize a model for characterizing and aggregating service groups, (2) develop a protocol for dynamic service aggregation, (3) identify a mapping for application requirements to service groups and network quality of service, (4) the establishment of a network access mechanism to support service degradation and scaling for multiple sessions, and (5) the simulation, implementation, and evaluation using established multipoint applications and multicast protocols.