Shuang Kai

A heuristic chunk scheduling algorithm reducing delay for Mesh-Pull P2P live streaming

Many Mesh-Pull P2P live streaming systems deployed in Internet catch a large number of users during recent years. While they have high scalability and low cost, they suffer from bad delay performance. In this paper, we aim at reducing the delay caused by chunk scheduling for Mesh-Pull P2P live streaming in the environment of heterogeneous upload bandwidth, heterogeneous and dynamic propagation delays. And we quantify and model the delivery latency of chunk scheduling as an optimization problem by introducing the propagation delay(usually ignored) between peers to the design of chunk scheduling, and put forward a heuristic pull-based chunk scheduling algorithm. Through simulation, our algorithm can adapt to random variance of propagation delays and outperform the two classical Mesh-Pull chunk scheduling algorithms not only in delay performance but also in chunk loss ratio.

Study on a Generic Service Description Model

Attractive services will be the crucial factor in the future competition of communication service providers. While system heterogeneity and service convergence complicate the service provisioning process, there are still no common models to support early service analysis. This paper proposes an implementation and network platform independent model for service description. It consists of four elements: EP (endpoint), LI (communication link), ELR (relations between endpoints and communication links) and LR (relations between communication links). We analyze the attributes of EP and LI which are static parts of a service and present ELR and LR by directed graphs which describe all possible behavior of the service. This model contains most basic properties used for requirements analysis and service architecture design, can support arbitrary number of users and one user can communicate with others in an arbitrary way. In the end, a multimedia conference service is described to verify the practicability of this model