Distributed Hash Table Structure Research Articles

Distributed Partition Detection With Dynamic Replication Management in a DHT-Based MANET

Curtailing the information loss due to network partitioning is imperative for the reliable communication in a distributed hash table (DHT)-based routing protocol for mobile ad hoc networks (MANETs). Both the limited transmission range and mobility of nodes cause recurrent network partitioning in MANETs that leads to an inaccessibility of the nodes’ mapping information, loss of the LID space, and partitioning of the DHT structure. To address the above-mentioned issues, this paper proposes a protocol that employs pre-partitioning measures, such as the critical link/node detection, the replication of the nodes’ mapping information, and so on, to augment the inter-node communication, but also reflects substantial improvement in the lookup delay. The proposed protocol effectively exploits the local neighbor information in a 3-D logical structure to identify/detect the critical nodes by employing a localized distributed algorithm. Simulation results show the significance of the proposed protocol in terms of end-to-end lookup delay, routing overhead, and success ratio.

An Efficient and Scalable Routing for MANETs

Recently, Distributed-Hash-Table (DHT)-based routing protocols have been proposed for large scale mobile ad hoc networks (MANETs). The motive behind using DHT is to avoid/reduce network wide flooding in MANETs in route discovery phase leading to achieve more scalable network. The challenge of deploying DHT at network layer for routing purpose in MANETs is to achieve more matching between logical and physical networks. The paper describes that existing DHT-based routing protocols for MANETs lack this feature. The paper presents a new DHT based scheme [called an efficient and scalable routing for MANETs (ESR)] which reduces the ill-matching between logical and physical networks. This is achieved be distributing the logical identifier (LID) space of DHT structure among the nodes such that the physical neighbors have consecutive LID space portions, i.e. all physical neighbors of a node are also the logical neighbors of the node. Therefore the logical ID space portion of a node may be non-contiguous. Based on this logical structure, a node builds up binary-search-tree (BST) using both logical ID space portion of itself and its neighbors. This BST at the node is traversed to find the next hop for a query/message. Through simulation, the paper shows the proposed approach (ESR) performs better than the existing one in term of routing overhead, average end-to-end delay, path-stretch values and false-negative ratio.

Improving playback quality of peer-to-peer live streaming systems by joint scheduling and distributed Hash table based compensation

In Peer-to-Peer (P2P) streaming systems, video data may be lost since peers can join and leave the overlay network randomly, thereby deteriorating the video playback quality. In this paper we propose a new hybrid mesh and Distributed Hash Table (DHT) based P2P streaming system, called HQMedia, to provide high playback quality to users by maintaining high data dissemination resilience with a low overhead. In HQMedia, peers are classified into Super Peers (SP) and Common Peers (CP) according to their online time. SPs and CPs form a mesh structure, while SPs alone form a new Streaming DHT (SDHT) structure. In this hybrid architecture, we propose a joint scheduling and compensation mechanism. If any frames cannot be obtained during the scheduling phase, an SDHT-based compensation mechanism is invoked for retrieving the missing frames near the playback point. We evaluate the performance of HQMedia by both theoretical analysis and intensive simulation experiments on large-scale networks to demonstrate the effectiveness and scalability of the proposed system. Numerical results show that HQMedia significantly outperforms existing mesh-based and treebased P2P live streaming systems by improving playback quality with only less than 1% extra maintenance overhead.

A Synergetic Pattern Matching Method Based-on DHT Structure for Intrusion Detection in Large-scale Network

Research in network security, with the attacks becoming more frequent, increasing complexity means, for the large-scale network intrusion detection, this paper presents a warning by analyzing the behavior of the log, the contents of the relevant association, through the DHT(Distributed Hash Table) distributed architecture, the Collabarative matching, fusion, and ultimately determine the method of attack paths. First, by improving the classical Apriori algorithm, greatly improving the efficiency of the association. At the same time, through the behavior pattern matching algorithms to extract information about the behavior of the alert and the behavior sequence elements to match the template, and through the right path to finally determine the value of the threat of the network path. After the design of a DHT network, the distributed collaborative match the path used to find complex network attacks. Finally, the overall algorithm flow, proposed a complete threat detection system architecture.

Load Balancing Scheme on the Basis of Huffman Coding for P2P Information Retrieval

Although a distributed index on a distributed hash table (DHT) enables efficient document query processing in Peer-to-Peer information retrieval (P2P IR), the index costs a lot to construct and it tends to be an unfair management because of the unbalanced term frequency distribution. We devised a new distributed index, named Huffman-DHT, for P2P IR. The new index uses an algorithm similar to Huffman coding with a modification to the DHT structure based on the term distribution. In a Huffman-DHT, a frequent term is assigned to a short ID and allocated a large space in the node ID space in DHT. Throuth ID management, the Huffman-DHT balances the index registration accesses among peers and reduces load concentrations. Huffman-DHT is the first approach to adapt concepts of coding theory and term frequency distribution to load balancing. We evaluated this approach in experiments using a document collection and assessed its load balancing capabilities in P2P IR. The experimental results indicated that it is most effective when the P2P system consists of about 30, 000 nodes and contains many documents. Moreover, we proved that we can construct a Huffman-DHT easily by estimating the probability distribution of the term occurrence from a small number of sample documents.