Collaborative Research: NeTS-NOSS: Networking the Digital Ocean

P.I.Mtira，Urbashi(USC)提案#：0520324协作机构：Presig(WHOI)提案#：0519903协作机构：Fall(Intel)提案#：0520040协作机构：Stojanovic(MIT)提案#：0520075 PROJECT标题：NETS-NOSS：联网数字海洋项目摘要天文台的科学工作将在很大程度上依赖于在所有类型的仪器、车辆、操作员、平台和传感器之间进行可靠通信的能力。这些活动将需要由仪器、传感器、机器人和车辆组成的综合网络协同工作，形成一个“数字海洋”。通过传播声信号进行水下通信是在海洋中进行可靠和通用无线通信的最好前景。近年来，在许多类型的海洋环境中建立物理层点对点链路方面取得了重大进展。然而，开发适合具有挑战性的海洋环境特点的高层技术在很大程度上仍是一个未被探索的领域。通过水声通信将“数字海洋”联网仍然是实现完全网络化海洋的巨大技术障碍之一。水声调制解调器和网络设计者要克服的挑战包括：与距离有关的带宽和衰减严重受限，广泛的时变多径传播，以及声音在水中传播的低速导致长传播延迟。对于传感器网络的部署，这些特征意味着必须考虑异步和自适应组网，典型的媒体接入控制将不可行，确定性算法可能由于水下网络的随机性质而不可行，以及链路质量预测和估计将对提供期望的服务质量至关重要。最后，依赖于距离的带宽意味着从容量分析到媒体访问控制的一切都必须在这些新的约束下重新开发。地面传感器网络的典型特征是节点密度高、大量潜在相关的传感数据、对系统资源的严格限制以及多个不确定源。水下传感器网络具有更强的局限性。为了实现海底传感器网络的目标，PIS提出了以下几个方面的研究：网络拓扑优化和估计，信道和能量感知路由，容忍延迟/中断的水下组网，结合水下信道特性的跨层设计，水声信道对标度律和基本限制的影响，水声组网系统概念的实验验证

P.I. Mtira, Urbashi (USC) Proposal #: 0520324Collaborating Institution: Presig (WHOI) Proposal #: 0519903Collaborating Institution: Fall (Intel) Proposal #: 0520040Collaborating Institution: Stojanovic (MIT) Proposal #: 0520075PROJECT TITLE: NeTS-NOSS: Networking the Digital OceanProject SummaryObservatory science efforts will rely heavily on the ability to communicate reliably between instruments, vehicles, operators, platforms, and sensors of all types. These activities will require integrated networks of instruments, sensors, robots, and vehicles to cooperate forming a "digital ocean." Underwater communication via propagating acoustic signals holds the best promise for reliable and general purpose wireless communications in the ocean. Significant advances have been made in recent years to establish physical layer point-to-point links in many types of ocean environments. Yet, the development of higher layer techniques suitable for the challenging characteristics of the ocean environment remains largely unexplored territory. Networking the "digital ocean" via underwater acoustic communications remains one of the formidable technical obstacles to the a fully networked ocean. Challenges to be overcome by underwater acoustic modem and network designers include: severely limited range-dependent bandwidth and attenuation, extensive time-varying multipath propagation, and low speed of sound propagation in water resulting in long propagation delays. For sensor network deployment, these features imply that asynchronous and adaptive networking must be considered, typical medium access control will not be feasible, deterministic algorithms may not be feasible due to the stochastic nature of underwater networks, and link quality prediction and estimation will be paramount to delivering the desired quality of service. Finally, distance-dependent bandwidth implies that everything from capacity analysis to medium access control must be redeveloped under these new constraints. Terrestrial sensor networks are typically distinguished by high node density, large amounts of potentially correlated sensed data, stringent limitations on system resources, and multiple sources of uncertainty. Underwater sensor networks have even stronger limitations. To achieve the goals of an undersea sensor network, the PIs propose to study the following: network topology optimization and estimation, channel & energy-aware routing, delay/disruption tolerant underwater networking, cross-layer designs which integrate underwater channel characteristics, impact of the underwater acoustic channel on scaling laws and fundamental limits, experimental validation of system concepts for underwater acoustic networking