We describe: (i) the architecture of an optical burst switched (OBS) demonstration network overlaying the ATDnet transparent all-optical testbed, and (ii) experiments underway in the testbed. The OBS overlay uses a simple hardware-based protocol embedded in OBS network controllers to manage commercial off-the-shelf DWDM switches. Data paths are all-optical and completely transparent, and can carry analog or digital traffic in any format, data rate, and modulation scheme. Experiments with latency-and jittersensitive HDTV transmission, petabyte file transfers, and immersive real time visualization of satellite imagery over the OBS network are ongoing. Parallel research on transport protocols, QoS-aware routing protocols, adaptors for an OBS LAN, and a network management architecture will be applied as completed. This is the first just-in-time (JIT) OBS field trial known to the authors.

SUMMARYAdvance reservation of lightpaths in grid environments is necessary to guarantee QoS and reliability. In this paper, we have evaluated and compared several algorithms for dynamic scheduling of lightpaths using a fl exible advance reservation model. The main aim is to fi nd the best scheduling policy for a grid network resource manager that improves network utilization and minimizes blocking. The scheduling of lightpaths involves both routing and wavelength assignment. Our simulation results show that minimum-cost adaptive routing where link costs are determined by the current and future usage of the link provides the minimum blocking. For wavelength assignment, we have used a scheme that reduces fragmentation by minimizing unused gaps. We have also analyzed approaches for failure recovery and resource optimization.

This paper describes innovative architectures and techniques for reserving and coordinating highly distributed resources, a capability required for many large scale applications. In the fall of 2006, Japan's G-lambda research team and the United States' EnLIGHTened Computing research team used these innovations to achieve the world's first inter-domain coordination of resource managers for in-advance reservation of network bandwidth and compute resources between and among both the US and Japan. The compute and network resource managers had different interfaces and were independently developed. Automated interoperability among the resources in both countries was enabled through various Grid middleware components. In this paper, we describe the middleware components, testbeds, results, and lessons learned.

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Many emerging high performance applications require distributed infrastructure that is significantly more powerful and flexible than traditional Grids. Such applications require the optimization, close integration, and control of all Grid resources, including networks. The EnLIGHTened (ENL) Computing Project has designed an architectural framework that allows Grid applications to dynamically request (inadvance or on-demand) any type of Grid resource: computers, storage, instruments, and deterministic, high-bandwidth network paths, including lightpaths. Based on application requirements, the ENL middleware communicates with Grid resource managers and, when availability is verified, co-allocates all the necessary resources. ENL's Domain Network Manager controls all network resource allocations to dynamically setup and delete dedicated circuits using Generalized Multiprotocol Label Switching (GMPLS) control plane signaling. In order to make optimal brokering decisions, the ENL middleware uses near-real-time performance information about Grid resources. A prototype of this architectural framework on a national-scale testbed implementation has been used to demonstrate a small number of applications. Based on this, a set of changes for the middleware have been laid out and are being implemented.