In contrast to traditional video, multi-view video streaming allows viewers to interactively switch among multiple perspectives provided by different cameras. One approach to achieve such a service is to encode the video from all of the cameras into a single stream, but this has the disadvantage that only a portion of the received video data will be used, namely that required for the selected view at each point in time. In this paper, we introduce the concept of a “multi-video stream bundle” that consists of multiple parallel video streams that are synchronized in time, each providing the video from a different camera capturing the same event or movie. For delivery we leverage the adaptive features and time-based chunking of HTTP-based adaptive streaming, but now employing adaptation in both content and rate. Users are able to change their viewpoint on-demand and the client player adapts the rate at which data are retrieved from each stream based on the user's current view, the probabilities of switching to other views, and the user's current bandwidth conditions. A crucial component of such a system is the prefetching policy. For this we present an optimization model as well as a simpler heuristic that can balance the playback quality and the probability of playback interruptions. After analytically and numerically characterizing the optimal solution, we present a prototype implementation and sample results. Our prefetching and buffer management solution is shown to provide close to seamless playback switching when there is sufficient bandwidth to prefetch the parallel streams.

We present an application of Integer Programming to the design of arrival routes for aircraft in a Terminal Maneuvering Area (TMA). We generate operationally feasible merge trees of curvature-constrained routes, using two optimization criteria: (1) total length of the tree, and (2) distance flown along the tree paths. The output routes guarantee that the overall traffic pattern in the TMA can be monitored by air traffic controllers; in particular, we keep merge points for arriving aircraft well separated, and we exclude conflicts between arriving and departing aircraft. We demonstrate the feasibility of our method by experimenting with arrival routes for a runway at Arlanda airport in the Stockholm TMA. Our approach can easily be extended in several ways, e.g., to ensure that the routes avoid no-fly zones.

Internet multimedia traffic currently occupies more than half of the total Internet traffic and it continues to expand tremendously. Targeting to meet strict constraints imposed by the requirements of real-time multimedia applications appropriate error-correction techniques should be implemented within the data dissemination network. We propose to introduce multipurpose relay nodes called Mediators into several positions within the tree networks typical for multicasting and broadcasting scenarios. By utilizing the error-correction domain separation paradigm in combination with selective insertion of the supplementary data from parallel networks, when the corresponding content is available, the proposed mechanism reduces the total network load and improves scalability of multicast/broadcast transmission. We share our view on how the existing application frameworks could benefit from the incremental deployment of the proposed mechanism. Experimental results confirm suitability and applicability of our assumptions.

We propose a scalable multicast architecture for potentially large overlay networks. Our techniques address suboptimality of the adaptive hybrid error correction (AHEC) scheme in the multicast scenarios. A hierarchical multi-stage multicast tree topology is constructed in order to improve performance of AHEC and guarantee QoS for the multicast clients. The multicast tree is divided into subtrees, called regions. Every region is assigned a control node, which serves the individual redundancy and retransmission requirements of the receivers within the region. Region sizes are bounded by the maximum cost per region, which defines the ability of the control nodes to serve the receivers of the assigned regions. We show that the multistage multicast architecture significantly reduces the amount of redundancy information introduced into the network and brings it closer to the Shannon bound.

Multi-interface mobile devices and multihomed residential Internet connections are becoming commonplace. However, standard transport protocols TCP and SCTP are unable to take advantage of several available paths so that the application using a single transport connection would receive the aggregate