Haitao Qu

A portion-based content distribution strategy in streaming media content distribution networks

Streaming media content distribution networks(SCDNS) are increasingly being used to disseminate data in todays Internet. A very important issue in SCDN is the content distribution strategy. This paper proposes a new content distribution strategy in which a content object was divided into two sections. The first part is replicated to all of cache server. The second part is replicated to a part of cache server. Compared with the strategy which take the content as a hole object, the clients perceive latency of the new strategy is low.

An Adaptive Service Composition Performance Guarantee Mechanism in Peer-to-Peer Network

Service composition is becoming a hot research point in recent years, especially in distributed peer-to-peer (P2P) network. However, how to guarantee the high-quality composition service performance becomes the key technology and difficulty in P2P network, which draws lots of attention in computer research field. According to the characteristics of distributed network, an adaptive service composition performance guarantee mechanism in P2P network is presented. Firstly, the composition services are divided into preferred service and backup one; secondly, BP neural network is introduced to detect and evaluate the service performance exactly; finally, the backup service will adaptively replace the preferred one when the preferred composition service performance is less than the threshold value. Except that, the half-time window punishment mechanism is introduced to increase the punishment to the low-quality service and encourage users to provide more high-quality one, which further improves the service composition performance in P2P network. The simulations verify our method to be effective and enrich the proposed theory. Keywords-service performance guarantee; BP neural network; adaptive mechanism; P2P network

A Network Coding Dynamic Node Selection Method in Mobile Peer-to-Peer Network

Analyzing the network coding and its application in mobile P2P network, a novel network coding dynamic node selection method in mobile Peer-to-Peer (P2P) network is proposed, which the hierarchical network structure divides the nodes into super node (SN) and ordinary node (ON). Considering the heterogeneous and dynamic characteristics, Part coding node (CN) selection program is adopted, which overcomes the defects of the current popular overall coding selection method. Comparing the centralized structure and overall distributed one, semi-distributed topology is used to balance the network load and maintain the unified management, which SN and ON is collaborated to manage network. Except that, the CN number evaluation mechanism based on feedback reflects the network environment changes, and can adjust the system parameter adaptively, which makes the whole system is fit for the real mobile P2P network. The simulations made by NS-2 verify the better performance of network coding than the traditional store- and-forward mechanism.

A Hierarchical and Heterogeneous P2P-SIP Architecture

In this paper, we propose a hierarchical and heterogeneous P2P-SIP architecture, which is independent of the underlying DHT overlay and makes the combination of P2P and SIP practical. Peers who work in heterogeneous overlays, i.e. Chord, Kademlia and Pastry, can intercommunicate with other peers who are in different overlay via a decentralized manner provided by the hierarchical P2P-SIP architecture. Some nodes in the overlay are proposed to be stateful to improve the reliability of the overlay. Finally, a session initial example is presented to illustrate this architecture.

A VoIP-based Dynamic Password Distribution Scheme

A VoIP-based dynamic password distribution scheme is described in this paper. For the respective drawbacks of the conventional dynamic password distribution schemes, a novel solution is proposed, the dynamic password is obtained by the user through making a call. The distribution system is based on a VoIP subsystem, of which the call control is modified to reduce the cost. The VoIP subsystem is designed on the basis of Asterisk and SIP protocol, both of which have outstanding advantages such as expansibility, business-oriented and so on. The architecture, workflow implementation and application of the dynamic password distribution system will be discussed in this paper.

A Self-Organizing Routing Model in Mobile Peer-to-Peer Based on Dynamic Region Management

The problem, such as low efficiency in discovering resource, high usage of network bandwidth, is caused by the frequent mobility of nodes in Peer-to-Peer network. A self-organizing routing model in mobile Peer-to-Peer base on dynamic region management is proposed by dint of our improved Meridian model. According to the mobility strength of nodes and introduction of dynamic management, the proposed algorithm overcomes the defects of original model and has more extensive application in actual mobile network environment. This proposed algorithm can quickly locate resource in mobile Peer-to-Peer; and performance analyses demonstrate the efficiency of the proposed algorithm.