Advances in Grid technology enable the deployment of data-intensive distributed applications, which require moving Terabytes or even Petabytes of data between data banks. The current underlying nehvorks cannut provide dedicated links with adequate end-to-end sustained bandwidth to support ihe requirements of these Grid applications. DWDM-RAM' is a novel service-oriented architecture, which harnesses the enormous bandwidth potential of optical nefivorks and demonstrates their on-demand nsage on the OMNlner. Preliminary experiments suggest that dynamic optical networks, such as the OMNlnet, are the ideal option for transferring such massive amounts of data. DWDM-RAM incorporates an OGSI/OGSA compliant service interface and will promote greater convergence between dynamic optical networks and data intensive Grid computing.

Meteor burst communication links rely on radiowave scattering from ionized trails left in the wake of meteors. Because of the significant path loss, on the order of 50 dB, associated with the trail‐scattering process, many means have been sought to improve link performance. Adaptive beam control algorithms and variable burst rate modems have been developed to achieve better use of the meteor burst (MB) channel. In addition to these techniques it is the contention of this paper that link performance may be further improved by making use of the spatial diversity inherent in meteor trails. Given the limited geographic extent of trail‐scattered signal footprints, adequately spaced receive sites can use different propagation paths associated with independent meteor trails from a single transmit site. The assumption here is that these receive sites are linked by a local communications network. The effective performance from the transmit site to any of the receive sites is significantly improved. Of course, this improvement is a function of receive site spacing and the performance of the short‐range network. This paper describes the meteor scatter phenomena that impact spatial diversity, details an approach for predicting the associated link performance improvement, and presents a sensitivity study based on computer model predictions.

Next generation applications and architectures (for example, Grids) are driving radical changes in the nature of traffic, service models, technology, and cost, creating opportunities for an advanced communications infrastructure to tackle next generation data services. To take advantage of these trends and opportunities, research communities are creating new architectures, such as the Open Grid Service Architecture (OGSA), which are being implemented in new prototype advanced infrastructures. The DWDM-RAM project, funded by DARPA, is actively addressing the challenges of next generation applications. DWDM-RAM is an architecture for data-intensive services enabled by next generation dynamic optical networks. It develops and demonstrates a novel architecture for new data communication services, within the OGSA context, that allows for managing extremely large sets of distributed data. Novel features move network services beyond notions of the network as a managed resource, for example, by including capabilities for dynamic on-demand provisioning and advance scheduling. DWDM-RAM encapsulates optical network resources (Lambdas, lightpaths) into a Grid Service and integrates their management within the Open Grid Service Architecture. Migration to emerging standards such as WS-Resource Framework (WS-RF) should be staright forward.In initial applications, DWDM-RAM targets specific data-intensive services such as rapid, massive data transfers used by large scale eScience applications, Extended abstractCommon architectures that underlie traditional data networks do not incorporate capabilities required by Grids. They are generally designed to optimize the relatively small data flow requirements of consumer services and the managed services of enterprises on a common core infrastructure oriented to the requirements of general, common communication services. Many Grid applications are data-intensive, requiring specialized services and infrastructure to manage efficiently multiple, large-scale data flows of multiple terabytes and even petabytes. Such capabilities are not effectively possible in traditional routed packet data networks. Typical Grid applications require the management of highly distributed resources within dynamic environments. Basic problems related to these requirements are common to almost all Grid environments, e.g., matching multiple, and potentially conflicting, application requirements to diverse, distributed 0-7803-8430-W04/$20,00 02004 IEEE 762

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