Peer-to-peer overlays constitute a new approach for delivering wide-area network and application services. The systems typically use a combination of self-organisation and cooperation with other peers to determine the peer’s role and performance in the overlay. Few overlays support external management mechanisms, which are the basis for overlay operators to provide specified service levels. We ...

One of the fundamental challenges in building Peer-to-Peer (P2P) applications is to locate resources across a dynamic set of nodes without centralised servers. Structured overlay networks solve this challenge by proving a key-based routing (KBR) layer that maps keys to nodes. The performance of KBR is strongly influenced by the dynamic and unpredictable conditions of P2P environments. To cope w...

The ever increasing demand of new applications has led researchers to propose new network architectures that address limitations of the current Internet. Given the rigidity of the Internet today, overlay networks are used to implement such architectures, in the hope of gaining a large user base. Despite sustained efforts to test and deploy new network architectures (on testbeds such as Planetla...

Performance of many P2P systems depends on the ability to construct a random overlay network among the nodes. Current state-of-the-art techniques for constructing random overlays have an implicit requirement that any two nodes in the system should always be able to communicate and establish a link between them. However, this is not the case in some of the environments where distributed systems ...

We present the extensions made to NEPI, the Network Experimentation Programming Interface, to allow easy creation and customization of routing overlays on top of PlanetLab. We particularly focus on demonstrating the traffic shaping capabilities provided by NEPI, with the use of customizable stream filters on PlanetLab overlays to induce controllable packet prioritization.

Introduction We present an image-guided surgical microscope system using augmented reality image overlays added onto one of the views of the operating microscope. With this system, segmented objects, outlines of risk regions, access pathways or 3D objects, previously extracted from preoperative tomographic images can be directly displayed as augmented reality overlays on the microscope image. R...