Mobile P2P Networks Research Articles

Analysis of P2P network system based on two‐stage service and failure repairability

SummaryAlong with the rapid development of the information technology revolution, P2P technology has been more and more widely and deeply researched in the field of mobile wireless, and mobile P2P has become an emerging and popular research field. The particularity of the mobile environment has extremely high requirements on the P2P network topology, resource transition paths and network security. In this paper, a two‐stage queueing model with negative customers and asynchronous failure is established based on a hybrid mobile network model combining the semi‐distributed topology and the fully‐distributed topology. Using the matrix‐geometric solution and Gauss‐Seidel iterative method, the probability distribution of the network model in steady‐state is obtained, and expressions for performance indicators such as the average number of peers in the two stages are given. Numerical experiments were conducted using programming software to analyze the effect of parameters on each indicator. The optimal parameters were solved by constructing the average cost unit time function and social benefit function to provide decision foundation for the mobile P2P network model.

IForest: An informed resource search strategy in mobile P2P networks

With the increasing applications of the mobile P2P networks, how to improve the resource search performance has been an important research focus. Peers’ features of strong mobility, short wireless transmission range and malicious behavior make the efficient and effective resource search more difficult in mobile P2P networks. This paper proposes an informed resource search strategy, iForest, in mobile P2P networks. To tackle the issue of peer’s mobility, we present a quantifying method of a neighbor peer’s stability; to deal with the problem of a peer’s malicious behavior, we employ the idea of peer’s credibility; to improve the resource search efficiency, we use the concept of peer’s resource accessibility. These guidance factors are derived and calculated based on the findings that each peer’s movements often repeat on a day-to-day basis and each peer has its own interests in mobile P2P networks. The simulation results showed that the iForest strategy could both improve the resource search success rate and reduce the communication complexity.

ZRR-P2P: Zone-Based Mechanism for Data Replication and Research Optimization in Unstructured P2P Systems

Peer-to-peer systems (P2P) have enjoyed great popularity in terms of sharing content in distributed environments. In mobile P2P networks, how to improve the efficiency of the resource lookup has been an important topic of research. Among the existing solutions, we find lookup mechanisms based on data replication that can increase data availability and reduce search latency. On the other side, these solutions have certain limits such as in the selection of resources to be replicated and in increasing the storage space of peers with additional data. Therefore, this work ZRR-P2P (Zone-based mechanism for data Replication and Research optimization in P2P) comes with the aim of partitioning the network zone on sub-zones and of replicating popular data shared in the network. Thus, in order to improve the research process without increasing storage space of peers. The simulation results show that our strategy manages to increase data availability and improve the search process in terms of hops count and search latency, while avoiding increasing the storage space of peers.

Analytical Comparison of Resource Search Algorithms in Non-DHT Mobile Peer-to-Peer Networks

One of the key challenges in ad-hoc networks is the resource discovery problem. How efficiently & quickly the queried resource/object can be resolved in such a highly dynamic self-evolving network is the underlying question? Broadcasting is a basic technique in the Mobile Ad-hoc Networks (MANETs), and it refers to sending a packet from one node to every other node within the transmission range. Flooding is a type of broadcast where the received packet is retransmitted once by every node. The naive flooding technique floods the network with query messages, while the random walk scheme operates by contacting subsets of each node’s neighbors at every step, thereby restricting the search space. Many earlier works have mainly focused on the simulation-based analysis of flooding technique, and its variants, in a wired network scenario. Although, there have been some empirical studies in peer-to-peer (P2P) networks, the analytical results are still lacking, especially in the context of mobile P2P networks. In this article, we mathematically model different widely used existing search techniques, and compare with the proposed improved random walk method, a simple lightweight approach suitable for the non-DHT architecture. We provide analytical expressions to measure the performance of the different flooding-based search techniques, and our proposed technique. We analytically derive 3 relevant key performance measures, i.e., the avg. number of steps needed to find a resource, the probability of locating a resource, and the avg. number of messages generated during the entire search process.

Analysis of threats and security issues evaluation in mobile P2P networks

Technically, mobile P2P network system architecture can consider as a distributed architecture system (like a community), where the nodes or users can share all or some of their own software and hardware resources such as (applications store, processing time, storage, network bandwidth) with the other nodes (users) through Internet, and these resources can be accessible directly by the nodes in that system without the need of a central coordination node. The main structure of our proposed network architecture is that all the nodes are symmetric in their functions. In this work, 
 the security issues of mobile P2P network system architecture such as (web threats, attacks and encryption) will be discussed deeply and then we propose different approaches and we analysis and evaluation of these mobile P2P network security issues and submit some proposal solutions to resolve the related problems with threats and other different attacks since these threats and attacks will be serious issue as networks are growing up especially with mobility attribute in current P2P networks.

Analysis and modelling the effects of mobility, Churn rate, node’s life span, intermittent bandwidth and stabilization cost of finger table in structured mobile P2P networks

Today P2P (Peer-to-Peer) networks are gaining popularity for sharing the contents. Due to massive spreading of Internet, these networks are also growing fast. MP2P (Mobile P2P) networks are attracting many users due to increase in the Internet-based mobile applications. These networks suffer from many challenges which are not considered for analysis and modelling adequately. We focus on few challenges like mobility of users, churn rate, intermittent bandwidth, shorter life span of mobile nodes, stabilization of finger table, etc. in this paper. We analytically analyse these challenges and define the effects of different parameters over the performance. Traditional P2P protocols are designed for wired networks and when these are implemented for mobile networks then mobility effect of users adds more challenge for researchers. We select two types of mobility models namely FF (Fluid Flow) and RWP (Random Waypoint) models to model the users’ mobility. The churn rate of the mobile nodes makes network overlay management and content searching more difficult in MP2P networks. We select finger table-based protocols which are widely deployed in the P2P networks. But these protocols can’t perform well in the mobile P2P networks due to mobility of the users. The mobility of the users and churn rate of the mobile nodes create failure in lookup of finger table and induce more cost to update the finger table. We consider these challenges and quantify the failure rate of mobile nodes, life span of mobile nodes, available bandwidth, cost of stabilization of finger table per node, etc. in this proposal. The proposed model is useful for modelling the performance of MP2P networks performance in various wireless environments like Mobile Ad hoc Networks (MANETs), Wireless Mesh Networks (WMNs), Wireless Sensor Networks (WSNs), Vehicular Ad hoc Networks (VANETs), Wireless LAN (WLAN), Wireless MAN (WMAN), etc.

PJ-Sec: secure node joining in mobile P2P networks

The advancement of portable mobile wireless devices such as smart-phones, PDA, etc., brought mobile peer-to-peer (P2P) as an extension of traditional P2P networks to provide efficient, low-cost communication among them in a cellular network. It is challenging to assign a unique identifier to each user, as an adversary can target to disrupt the P2P system, by carefully selecting user IDs or obtaining many pseudo-IDs. This work proposes a robust node-ID assignment mechanism for secure peer joining in mobile P2P system called PJ-Sec. PJ-Sec facilitates to generate nodeID for a joining peer by a collaborative effort of an existing peer (within the vicinity) and pre-selected vicinity head. PJ-Sec is formally analyzed using AVISPA model checker and found to be attack resistant.

Anchor Vertex Selection for Enhanced Reliability of Traffic Offloading Service in Edge-Enabled Mobile P2P Social Networks

As the rapid growth of mobile social networks, mobile peer-to-peer (P2P) communications and mobile edge computing (MEC) have been developed to reduce the traffic load and improve the computation capacity of cellular networks. However, the stability of social network is largely ignored in the advances of P2P and MEC, which is related to the social relations between users. It plays a vital role in improving the efficiency and reliability of traffic offloading service. In this paper, we integrate an edge node and the nearby P2P users as a mobile P2P social network and introduce the problem of adaptive anchored (k,r)-core to maintain the stability of multiple mobile P2P networks. It aims to adaptively select and retain a set of critical users for each network, whose participation is critical to overall stability of the network, and allocate certain resource for them so that the maximum number of users of all networks will remain engaged and the traffic of cellular network can be minimized. We called the retained users as anchor vertices. To address it, we devise a peer-edge-cloud framework to achieve the adaptive allocation of resources. We also develop a similarity based onion layers anchored (k,r)-core (S-OLAK) algorithm to explore the anchor vertices. Experimental results based on a real large-scale mobile P2P data set demonstrate the effectiveness of our method.

Improving peer coordination quality in mobile P2P networks considering peer awareness and group synchronization: Implementation and performance evaluation of two fuzzy-based systems

Improving peer coordination quality in mobile P2P networks considering peer awareness and group synchronization: Implementation and performance evaluation of two fuzzy-based systems

Fuzzy-Based 3-D Stream Traffic Lightweighting Over Mobile P2P Network

Supporting the huge amount of network traffic from three-dimensional (3-D) streaming is an extremely important challenge, as 3-D streaming has the potential to cause network congestion and longer waiting times. These problems can also lead to 3-D video being blurred, and negatively affecting the user experience. This article uses the front camera of a mobile device to track a user's viewing angle, and then calculates the currently needed 3-D stream to find the most suitable peer for video source supply. This article also considers several impact factors to choose supply partners with different data flow via fuzzy theory. Consequently, the proposed method is able to determine the best way to download the desired 3-D stream without unnecessary congestion, thus maintaining the overall peer-to-peer network quality. Simulation results show that the proposed method can reduce the quantity of the video flow, while maintaining video quality, thus avoiding bottlenecks like bandwidth and network speed.

Local P2P group (LPG) communication in structured mobile P2P networks

With the onset of the digital era and the availability of the internet, the need for digital data in a huge manner can be fulfilled by peer-to-peer (P2P) network instead of a traditional client server-based solution. Generally, mobile communication is based on cellular networks or multi-hop wireless networks. Cellular networks have adequate fixed infrastructure whereas multi-hop wireless networks have limited infrastructure and hence there are many limitations. The P2P systems are mainly designed for wired networks and the routing is based on IP infrastructure. Chord based protocols are widely deployed in the structured P2P networks but it can not perform well when implemented for mobile P2P networks due to the mobility of the users. Mobility pattern of mobile users plays an important role in locating users and delivering data packets seamlessly. Today, many of the mobile users follow a fixed mobility pattern in urban cities and mobility pattern of the mobile users can be utilized to reduce table update cost and increase Lookup Success Rate (LSR). We have proposed Local P2P Group (LPG) based communication scheme for structured mobile P2P networks. We are focussed on the mobility pattern of the mobile users in urban cities. We have analytically evaluated the proposed scheme using fluid-flow and RWP (Random Waypoint) mobility models and found that the proposed scheme performs better than the existing schemes like MR-Chord and MobiStore. Our proposed scheme has up to 40% higher Lookup Success Rate and 81% less table update cost than existing schemes, MR-Chord and MobiStore.

Mobility Pattern Based Chord (MP-Chord) for Enhanced Lookup Performance in Mobile P2P Networks

The peer-to-peer (P2P) systems are mainly designed for wired networks. These networks suffer from many challenges like malicious content distribution, free riding, whitewashing, poor search scalability, lack of a robust trust model, etc. The churn of the nodes makes topology management and searching resource more puzzling. When P2P protocols are implemented for mobile networks, it adds more challenges, specially the mobility management of the mobile users, intermittent connection, and limited bandwidth. Chord based protocols are widely deployed in the P2P networks but Chord can’t perform well in the mobile P2P networks due to mobility of the users. The frequent join and depart of the mobile users creates Chord lookup failure and induces more cost to maintain the finger table. The mobility pattern of the mobile users can be considered to enhance of the Chord lookup performance for mobile P2P networks. It has been observed that most of the mobile users in the urban cities follow fixed mobility pattern which can be utilized to enhance the Chord performance. We have proposed a Mobility Pattern based Chord (MP-Chord) scheme for structured mobile P2P networks. We have presented analytical modelling and performance analysis of the proposed scheme and existing schemes and found that the proposed scheme performs better than the existing Chord-based schemes for mobile P2P networks.

CRAM: Clustering-based Resource Availability Measurement in Mobile Peer-to-Peer Systems

The peer-to-peer (P2P) systems are an alternative to solve the scalability issue raised by the client/server systems. P2P systems are composed of a set of entities that communicate directly without any central server and constitute scalable and robust distributed systems. In these systems, an entity only has a partial knowledge about the overlay state. The challenge is to provide a global knowledge in the system regarding a feature as the resources availability. In this paper, we propose a clustering-based resource availability measurement called CRAM for mobile P2P networks which relies on knowledge from all entities. CRAM can be used in resource search and in replication strategies to improve the network performances. Simulation results show that our estimation of availability is close to the real one such as the deviation between them can equal 0.008. They also show that our algorithm reacts efficiently to the appearance or depletion of a resource replica in the system.

CRAM: clustering-based resource availability measurement in mobile peer-to-peer systems

The peer-to-peer (P2P) systems are an alternative to solve the scalability issue raised by the client/server systems. P2P systems are composed of a set of entities that communicate directly without any central server and constitute scalable and robust distributed systems. In these systems, an entity only has a partial knowledge about the overlay state. The challenge is to provide a global knowledge in the system regarding a feature as the resources availability. In this paper, we propose a clustering-based resource availability measurement called CRAM for mobile P2P networks which relies on knowledge from all entities. CRAM can be used in resource search and in replication strategies to improve the network performances. Simulation results show that our estimation of availability is close to the real one such as the deviation between them can equal 0.008. They also show that our algorithm reacts efficiently to the appearance or depletion of a resource replica in the system.

Priority Scheme for Enhancing the Capacity of Peer-to-Peer Networks in Mobile Environments

Given the pervasive use of wireless systems, based on the IEEE 802.11 and LTE standards, Peer-to-Peer (P2P) networks take relevance due to their inherent flexibility and scalability. In a mobile environment, users experience different channel conditions. This has a major impact on the system’s performance as it is perceived by users in different coverage zones. Additionally, users have different degrees of mobility which can improve or degrade the quality of the received signal. In this work, a wireless mobile P2P network is studied. Building on this, two different scenarios are considered. Namely, a WLAN environment where nodes usually know the placement of the access point and can move closer to it in order to improve their channel quality and a cellular system where nodes usually do not know where their attending base station is located. Building on this, a priority model to improve the system’s performance is proposed, studied and analyzed. This priority scheme is based on serving first users that experience a better channel condition in order to improve the file downloading process. The aforementioned networks are analyzed using both a fluid model and a Continuous Time Markov Chain.

Black Hole Attack Prevention in Wireless Peer-to-Peer Networks: A New Strategy

Mobile peer-to-peer networking (MP2P) is a relatively new paradigm compared to other wireless network technologies. In the last 10–15 years, it has gained tremendous popularity because of its usefulness in applications such as file sharing over the Internet in a decentralized manner. Security of mobile P2P networks represents an open research topic and a main challenge regarding the vulnerability of these networks and their convenience to different security attacks such as black hole, Sybil, etc. In this work, we analyze the black hole attack in wireless P2P networks using the AODV as the routing protocol. In a black hole attack, a malicious node assumes the identity of a legitimate node, by creating forged answers with a higher sequence number, and thus forces the victim node to prioritize it as a relay node. We propose a solution based on a modification of the AODV routing protocol, taking into account the behavior of each node participating in the network. The performances of our proposal are evaluated by simulation.

A mobility-aware approach for distributed data update on unstructured mobile P2P networks

In unstructured mobile peer-to-peer systems (MP2P), the frequent link breakages lead frequent topology mismatching problems and data transmission failures due to high mobility of nodes. The overhead of data transmission and synchronization cannot be neglected. In order to keep the data consistent, flooding is a fundamental and straightforward data synchronization mechanism since a mobile node does not know which else has the same shared data item. However, data flooding causes the broadcast storm problem. In this paper, we propose a mobility-aware data update approach (MADU) to improve the data dissemination and to reduce the overhead of maintaining the consistency of shared data items in an MP2P network. We use safe-time which is derived from the neighbor’s location and speed to determine the time for a node to do the checking and updating between the neighbor nodes and itself. We also consider the network connectivity of a mobile node and access frequency of a data item as the factors to trigger the update process. By combining the mobility information of nodes, network connectivity, and access frequency of data items, we set a reasonable data update mechanism, which can significantly decrease the number of retransmissions and redundant messages so as to reduce the overhead of maintaining the data consistency.

Addressed Query Gossip Resource Discovery Protocol for Mobile P2P Networks and Its Performance in Diverse Mobility Models

This article describes how P2P resource discovery protocols perform poorly over mobile ad hoc networks mainly due to the frequent network dynamics. Peer-to-Peer search techniques including structured and unstructured can be employed over MANETs. Empirical studies indicate that searching in such resultant networks are not efficient and effective due to peer discovery, connectivity and mobility issues. The author proposes Addressed Query Gossip Resource Discovery algorithm, a lightweight resource discovery designed to suit the mobility requirements of ad hoc networks to optimize the search performance while at the same time minimize the extra usage of mobile and network resources. Mobility models represent the movements of mobile nodes. Such models are used to represent how the location, velocity and acceleration change over time. The author conducts performance analyses of the proposed protocol and widely used unstructured search techniques over MANET under 2 realistic mobility models, i.e., Random Waypoint and Reference Point Group Mobility models. The results show that the proposed protocol has the best performance in almost every measured metrics. In addition, the protocol consumes less energy, has less message overhead and good success ratio for random waypoint movement as compared to the reference group mobility model. After extensive evaluations, the simulation results clarify that the mobility models have a significant impact on the performance of peer-to-peer content discovery protocols over mobile ad hoc networks.

Cooperative Caching for Efficient Data Search in Mobile P2P Networks

In this paper, we propose a cooperative caching scheme for structured data via clusters based on peer connectivity in mobile P2P networks. In the proposed scheme, a cluster is organized for cache sharing among mobile peers with long-term connectivity, and metadata are disseminated to neighbor peers for efficient data search performance. It reduces data duplication and uses cache space efficiently through integrative cache management of peers inside the cluster. The proposed scheme reduces data replacement time in the event of changes in topology or cache data replacement using the concept of temp cache. It performs data recovery and cluster adjustment through cluster management in the event of an abrupt disconnection of a peer. In the scheme, metadata of popular data are disseminated to neighbor peers for efficient data searching. In a data search, queries are processed in the order of local cache, metadata, the cluster to which it belongs, and neighbor clusters, in accordance with cooperative caching strategy. Performance evaluation results show that the proposed scheme has a higher cache hit ratio, and lower cost for data replacement and query processing than existing schemes.

Cooperative caching for multimedia data in mobile P2P networks

In this paper, we propose a cooperative caching scheme for multimedia data via clusters based on peers connectivity in mobile P2P networks. In the proposed scheme, a cluster is organized for cache sharing among mobile peers with long-term connectivity, and metadata are disseminated to neighbor peers for efficient multimedia data search performance. It reduces data duplication and uses cache space efficiently through integrative cache management of peers inside the cluster. The proposed scheme reduces data replacement time in the event of changes in topology or cache data replacement using the concept of temporal cache. It performs data recovery and cluster adjustment through cluster management in the event of an abrupt disconnection of a peer. In this scheme, metadata of popular multimedia data are disseminated to neighbor peers for efficient data searching. In a data search, queries are processed in the order of local cache, metadata, the cluster to which it belongs, and neighbor clusters, in accordance with cooperative caching strategy. Performance evaluation results show that the proposed scheme has a higher cache hit ratio, and lower cost for data replacement and query processing than existing schemes.