Sandeep K. Singhal

P2P-IM: A P2P Presence System for the Internet

Traditional instant messaging applications rely on central server infrastructure to broker user information. The cost and complexity of this infrastructure makes it difficult for developers to build and deploy lightweight presence and instant messaging systems within their own applications. In this paper, we describe P2P-IM, a peer-to-peer instant messaging client that does not rely on any hosted server infrastructure. The system provides the rich facilities available from traditional client-server systems but enables easy deployment and integration with existing applications. The solution provides simplified identity generation, connectivity, and rich per-application data publication.

Scalable networked virtual environments using unstructured overlays

Large-scale Networked Virtual Environments (NVEs) are used to enable rich interactive experiences such as multiplayer games, military and industrial training, and collaborative engineering systems. In these applications, hosts must exchange data updates to maintain a consistent view of the virtual environment. In large-scale environments, the volume of data places a heavy load on the networking and computational resources available to each host. To improve scalability, systems have employed a variety of techniques, including data subscription, data segmentation, and multicast. In this paper, we describe a communication architecture for Networked Virtual Environments that takes advantage of unstructured peer-to-peer (P2P) overlay networks for message distribution. The overlay network design provides scalability while supporting easy deployment over todays Internet. The approach, when combined with data segmentation and data subscription, enables Internet deployment of large-scale NVEs.

Internet Scale Testing of PNRP Using WiDS Network Simulator

PNRP (peer name resolution protocol) is a decentralized name resolution and routing protocol built into the Windowstrade operating system that creates an Internet-scale peer-to-peer structured overlay. Ensuring the protocols performance in Internet scale presents a critical challenge. We describe Internet scale testing of PNRP using a distributed network simulator, WiDS. We use real-world Internet characteristics and PNRP node behaviors to simulate the Internet environment, assess PNRP performance, and support protocol debugging. A case study demonstrates identification of a protocol flaw that could otherwise only be discovered through full-scale deployment experience

Private Peer-to-Peer Overlay for Real-Time Monitoring of a Deployed Internet-Scale Peer-to-Peer Overlay

Traditional instant messaging applications rely on central server infrastructure to broker user information. The cost and complexity of this infrastructure makes it difficult for developers to build and deploy lightweight presence and instant messaging systems within their own applications. In this paper, we describe P2P-IM, a peer-to-peer instant messaging client that does not rely on any hosted server infrastructure. The system provides the rich facilities available from traditional client-server systems but enables easy deployment and integration with existing applications. The solution provides simplified identity generation, connectivity, and rich per-application data publication.Peer-to-peer system decentralization complicates performance monitoring-and real-time monitoring is particularly challenging. We discuss our experience with monitoring the Peer Name Resolution Protocol (PNRP), a peer-to-peer name resolution/routing protocol and overlay deployed over the Internet. We must collect accurate performance data without adding traffic overhead. Unfortunately, no central node has sufficient monitoring information, and scalability and privacy concerns make it impractical to collect reliable real-time data from active client nodes. Our method obtains information from lightweight nodes (Weather Stations) actively deployed on the P2P network and themselves forming a private P2P overlay. We monitor the overall performance of the PNRP protocol on the Internet and produce timely reports supporting network management, security alerting, and system maintenance.