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As grid applications evolve, the need for user controlled network infrastructure is apparent in order to support emerging dynamic and interactive services. Due to the inherent bandwidth offered by optical wavelength division multiplexed (WDM) networks, they prove to be a potential candidate to support the bandwidth intensive grid applications. In a grid environment, the available resources can be classified into two broad categories: grid resources which consist of computing and storage components that reside on each node of the network and network resources which provide bandwidth for the execution of a grid application. A typical grid application (job) is usually divided into a number of smaller tasks which need to be scheduled, on possibly different nodes of the network in order to ensure job completion. There usually exists some dependency between these tasks and a strict time-deadline within which the job needs to be completed. Rather than using an independent scheduling approach (at the grid and network levels), we address the co-scheduling problem in lambda-grids for advance reservation requests and aim at minimizing the job blocking probability. We use the anycasting communication paradigm referred to as co-anycasting, to allocate grid and network resources to all tasks of a job. We propose three heuristics: first free (FF), shortest hop (SH), and least used (LU) to solve the co-scheduling problem. Moreover, we compare the proposed co-anycasting approach to a grid-anycasting approach, wherein the anycasting flexibility is offered only at the grid level, and show through extensive simulations the performance benefit of using co-anycasting to support grid applications in a time-deadline environment. [ABSTRACT FROM PUBLISHER]

In this paper we investigate the multicast advance reservation problem in wavelength division multiplexed (WDM) optical networks. Under the advance reservation traffic model (also know as scheduled traffic), connection requests specify their start time to be some time in the future and also specify their holding times. Traditionally, in WDM networks, the multicasting functionality is supported by assuming that the optical cross connects are multicast capable i.e., they are capable of switching an incoming signal to multiple output interfaces. To support the multicasting functionality in a multicast incapable (MI) network, one can use a naive approach of creating a virtual topology consisting of wavelength routes (lighpaths) from the multicast source to each destination of the multicast session. This approach tends to consume a lot of network bandwidth and may become unacceptable as the number of the multicast sessions increase. We refer to this approach of provisioning the multicast requests as Multicast via WDM Unicast (MVWU) approach. To efficiently provision the users' scheduled multicast requests in a MI network, we propose two overlay solutions: Drop at Member Node (DAMN) and Drop at Any Node (DAAN). In these solutions, we achieve multicasting by creating a set of lightpath routes (possibly multiple hops) in the overlay layer. We consider a static set of scheduled multicast requests and present integer linear programs (ILPs) to solve the DAMN and DAAN problems, with a goal to minimize the total number of wavelengths required to service the request set. We also present an efficient heuristic and compare its performance to the ILP for a small network, and evaluate its performance for large-scale networks. Moreover, we also present an ILP to solve the naive MVWU approach and compare its performance to the DAMN and DAAN1. [ABSTRACT FROM PUBLISHER]