In-network caching is frequently used to reduce unnecessary network traffic and lower server workload by allowing content to be accessed from the caching nodes in both wired and wireless networks. The drastic increasing mobile data traffic demands have conceived cooperative content sharing between nodes for addressing the storage limitation of a single node. In this paper, we explore the problem of minimizing transmission cost among cooperative nodes by jointly optimizing caching and routing in a hybrid network with vital support of service differentiation. We show that the optimal routing policy is a route-to-least cost-cache (RLC) policy for fixed caching policy. We formulate the cooperative caching problem as a Markov decision process (MDP) with the goal of maximizing the long-term average caching reward, which is NP-hard even when assuming users demands are perfectly known. Our study then proposes C-MAAC, a collaborative multi-agent deep reinforcement learning (MADRL) algorithm employing actor-critic learning model. C-MAAC has a key characteristic of centralized training and decentralized execution, with which challenge from the unstable training process caused by simultaneous decision of all agents can be addressed. After completing the offline training process, each node independently makes caching decision online during the execution process. Simulation results demonstrate the effectiveness of our proposed algorithms under dynamic environment where user request traffic change rapidly.

The move towards sixth-generation (6G) is expecting to support not only more device connections but also the soaring multimedia big data traffic demands, which spawns the promising approach of in-network caching of information centric networks (ICN) in Internet of Things (IoT). By prefetching popular contents during off-peak traffic periods, caching nodes can make them available to users during peak periods, effectively improving the quality of experience. In this paper, considering the limited cache capacity, unknown popularity distribution as well as non-stationary user demands, we explore this problem by optimizing content caching with the objective of minimizing long-term transmission cost. The content caching process is modeled as a cooperative Markov decision process (MDP), aiming to maximize caching reward. To handle this optimization problem, we propose a deep Q network-based content caching (DQN-CC) algorithm to obtain the approximate optimal solution in an online fashion, thus the agent at the controller is able to adaptively learn and track the underlying dynamics. To update the cache of each node, a replacement rule based on the marginal gain is used, offering faster update and reduced complexity. Extensive simulations verify the superiority of the introduced design.

With the continuous development of autonomous vehicles, telemedicine, digital media and other time-sensitive applications, a soaring number of network services have high demand for the quality of service (QoS) with extra low delay and jitter. Traditional network architecture only offers best-effort services which cannot meet the stringent delay and jitter requirements. In this paper, we propose a resilient-priority queue scheduling algorithm (RPQ) for delay-sensitive services. RPQ can guarantee stable delay in a fine-grained manner. Particularly, on the premise of meeting the delay requirements of high priority streams, RPQ can give consideration to the delay requirements of lower priority streams depending on its resilient scheduling mechanism. We implement RPQ on programmable switch. The experimental results show that RPQ not only guarantees QoS with low delay and low jitter for delay-sensitive streams but also improves network throughput by comparing with the existing solutions, i.e., SP-PIFO and WRR.

Traditional routing technologies based on a single IP address domain faces the challenge to meet the increasing demand for network services and security. Packet classification is a technique to differentiate multi-domain network traffic in a fine-grained manner using packet header fields. Packet classification requires to operate efficiently to avoid it becoming a bottleneck in the packet routing process. Tuple space search (TSS) used in SDN supports fast rule updates but low-speed packet classification. In this paper, we propose a learned Bloom filter (LBF)-based packet classification algorithm that combines LBF and TSS to promote classification speed by avoiding invalid hash table accesses. Specifically, LBF consists of multiple RNN models and one support Bloom filter (SBF), in which the learned models are trained with the positive and negative sets, and used as a pre-filter to identify the two sets. For the filter outcomes with a negative result from learned models, SBF is constructed to perform the second filtration. To ensure efficiency of RNN and SBF, we carefully select key features to be used in RNN and SBF, which can also maintain efficient search in the final stage of hash checking. Our experimental results show that the proposed algorithm saves more memory space than Tuple space pruning (TSP) given the same false positive rate. The proposed algorithm is competitive in terms of the number of memory accesses, while achieving almost one order of magnitude improvement on pre-processing time over NeuroCuts which is an advanced decision tree classifier.

With the development of communication technologies, vehicular network applications have evolved from basic traffic safety and efficiency applications to information and entertainment applications. The implementation of emerging vehicular applications is based on the efficient dissemination of multimedia data. In view of the dynamic topology changes, severe channel fading and limited spectrum resources of vehicular networks, how to achieve efficient multimedia data dissemination in the harsh network environment is an urgent problem. Based on the hybrid cellular-D2D vehicular network, this paper proposes a cluster-based cooperative multicast scheme. The scheme combines multicast transmission with D2D-assisted relay technology to provide high-quality data dissemination for vehicle users under limited spectrum resources. In this paper, we innovatively present a communication quality index that considers multiple performance factors and formulate the relay selection problem as the anti p-center problem in graph theory. Then we propose a heuristic method to solve the problem. The results show that the proposed scheme can effectively improve the utilization of wireless resources and the success rate of data dissemination.

With the increasing popularity of terminals and applications, the corresponding requirements of services have been growing significantly. In order to improve the quality of services in resource restrained user devices and reduce the large latency of service migration caused by long distance in cloud computing, mobile fog computing (MFC) is presented to provide supplementary resources by adding a fog layer with several servers near user devices. Focusing on cloud-aware MFC networks with multiple servers, we formulate a problem with the optimization objective to improve the quality of service, relieve the restrained resource of user device, and balance the workload of participant server. In consideration of the data size of remaining task, the power consumption of user device, and the appended workload of participant server, this paper designs a machine learning-based algorithm which aims to generate intelligent adaptive strategies related with load balancing of collaborative servers and dynamic scheduling of sequential tasks. Based on the proposed algorithm and software-defined networking technology, the tasks can be executed cooperatively by the user device and the servers in the MFC network. Besides, we conducted some experiments to verify the algorithm effectiveness under different numerical parameters including task arrival rate, avaliable server workload, and wireless channel condition. The simulation results show that the proposed intelligent adaptive algorithm achieves a superior performance in terms of latency and power consumption compared to candidate algorithms.

Content-Centric Networking (CCN) has emerged as a promising paradigm in current Internet Due to the interest-driven, we concern more about the content itself rather than the place it located, and therefore, CCN supports subscriber mobility natively, however, it remains a major challenge in publisher mobility. In this paper, we propose a hierarchical mobility management scheme for CCN (HMMCCN) which contains an overlay mapping structure to store the old-to-new name binding relationship and perform the mobility management for mobile nodes. The main goals of this paper are: (a) to propose a mobility scheme suitable for all mobile nodes in CCN, both publishers and subscribers; (b) to describe the hierarchical mobility management procedure during intra-domain and inter-domain handoff; (c) to establish an analytical model and formulate the location update signaling cost.

Recent work has shown that Proxy Mobile IPv6 (PMIPv6) is a promising mobility management protocol for its salient features, such as supporting unmodified Mobile Node (MN). However, PMIPv6 does not consider the multicast routing support. Moreover, current research mainly concerns on the multicast receiver mobility, but it is a critical and challenging issue to ensure service connectivity for mobile multicast senders, which has not been addressed well. In this paper, we propose an efficient multicast sender mobility scheme for PMIPv6 (PMIP-BT), in which the multicast data can be transmitted through the PMIPv6 tunnel and the multicast sender mobility is transparently enabled in the PMIPv6 networks. Numerical results show that the proposed scheme outperforms the current scheme in terms of signaling cost.

The original architecture of content-centric network CCN may suffer from interest flooding attacks. In this paper, we focus on one type of interest flooding attacks called denial of service against content source DACS attack. To damage CCN, it floods a large number of malicious interests requesting content that does not exist, which guarantees that no cache hit can occur at routers until these malicious interests reach the target content source. Thus, it can directly exhaust the resource of the victim. To counter it, we propose a threshold-based detecting and mitigating TDM scheme. The basic idea is to detect DACS attack on the basis of the frequency that pending interest table items in CCN routers expire recording this frequency by introducing two counters with their corresponding thresholds and one indicator for counter mode and to mitigate it by implementing the rate limiter in each router. From the viewpoint of a CCN router, we analyze the performance of TDM in terms of detection ability and effect on mitigating malicious traffic. In addition, we briefly analyze the overhead of TDM. The results show that TDM achieves high detection ability and good effect on mitigating malicious traffic while bringing in small overhead on countering DACS attack. To the best of our knowledge, this is the first attempt to design a detailed scheme embedded with corresponding algorithms on countering this attack. Copyright © 2013 John Wiley & Sons, Ltd.

With the growth of different design goals and application requirements, wireless sensor networks (WSNs) are receiving sustained attentions in the recent low-cost industrial automation systems. Moreover, Cognitive Radio (CR) technology gives us a possibility to maximize the utilization efficiency of the limited spectrum resources. However, because the wireless devices coexist in the same radio environment, there are harmful channel conflicts among users, and the increasing radio systems causes great contribution to the increasing energy consumption. In order to realize the industrial circumstance, we complete three major works in this paper. First of all, we describe a practical model of cumulative interferences from the entire cognitive radio-based industrial wireless sensor networks (CR-IWSNs). Then, based on the interference model and the interference avoidance purpose, we propose a self-configurable power control scheme to address the communication requirements on both interference temperature and secondary network Quality-of-Service. Finally, Nonlinear Programming is used to model the scheme and a distributed algorithm is given to solve the problem. Several simulations are given to verify the effectiveness of the proposed power control algorithm on optimizing the total system throughput and energy consumption. Results show that the throughput could be improved and the energy consumption could be reduced with the guarantee that the users are without interference.

With the success of wireless technologies and the number of wireless devices increasing, the wireless coverage footprint expands and removes the needs of wired networks for industrial applications. Wireless industrial sensor networks (WISNs) are a type of wireless sensor networks (WSNs), which dedicate to industrial applications. The WISNs bring several advantages over traditional wired industrial networks for detection and control, include flexibility, scalability, remote maintenance, and rapid deployment. However, some technical issues and routing design principles need to be noticed in terms of the stringent requirements of industrial applications. In this paper, we firstly introduce the characteristics and some routing issues of WISNs. Then we discuss existing routing protocols for WISNs and analysis their performances. Finally, we outline several future research directions.

As a promising network-based mobility management method that does not require active participation of mobile nodes (MNs), Proxy Mobile IPv6 (PMIPv6) is attracting considerable attention among the telecommunication and Internet communities. It remains an open issue how to build a scalable PMIPv6 domain that is able to support a large number of MNs while keeping handover delays low. In this paper, we propose an approach for building Scalable And Robust PMIPv6 (SARP) domains. We propose that every mobility access gateway (MAG) in a SARP domain also functions as a local mobility anchor (LMA), and is organized into a virtual ring with all other MAGs. Consistent hashing is used to efficiently distribute the mapping between each MN and its LMA to all MAGs. A MAG finds an MN's LMA by sending a query message to the virtual ring. Our analysis verifies the robustness and scalability of SARP. We also propose two handover procedures for SARP and show that they achieve low handover delays.

Abstract Mobile IPv6 (MIPv6) is a host‐based mobility support specification which has been approved by the IETF as the standardized solution of global mobility management in IPv6 network for Mobile Node (MN). However, MIPv6 handover procedure results in a large handover delay. To improve its performance, some MIPv6 variants such as Fast Handover for MIPv6 (FMIPv6) and Hierarchical MIPv6 (HMIPv6) were proposed. However, they all require the MN to support the mobility management protocols which increase the difficulty of management and deployment. Recently, IETF NETLMM workgroup published the Proxy Mobile IPv6 (PMIPv6) which is a network‐based localized mobility management to provide the mobility support for mobile host without the involvement of the mobility signaling. In this paper, we analyze the singling cost of PMIPv6 and implement it in our test‐bed to evaluate its performance. The results show that the PMIPv6 has lower signaling cost and packet delivery cost, and it can improve the handover performance of UDP and TCP than the other mobility management protocols under low‐delay networks, as for the wide area networks, it needs to introduce some mechanism like fast handover to further improve its performance. Copyright © 2009 John Wiley & Sons, Ltd.

Wireless sensor network (WSN) is the connection between the physical world and mankind. Particularly, environmental monitoring and devices automatic control of intelligent building based on wireless sensor network is considered as one of the most crucial applications. It can perceive many kinds of environmental parameters and feedback control information to some devices to provide comfortable environment to people. However, it is difficult to deploy a WSN in the buildings because there usually are many wireless LAN devices used in the buildings, which bring serious frequency interferences. In this paper, we conduct a real intelligent building wireless sensor network (IBWSN) for environmental monitoring and air-conditioning automatic control. In order to ensure the effectiveness of this system, actual spectrum analysis is developed. Performance evaluation proves that the presented IBWSN can satisfy the needs of the proposed applications.

Abstract Proxy mobile IPv6 (PMIPv6) is a network‐based mobility protocol where the mobility management signaling is performed by a network entity on behalf of the node requiring mobility itself. To the best of our knowledge, no studies have been conducted in the area of proxy MIPv6 authentication method. This paper proposes an authentication method in proxy MIPv6. In addition to providing access authentication, the proposed authentication method prevents threats such as replay attack and key exposure. Also, we develop analytic models for the authentication latency and cost analysis. Then, the impacts of mobility and traffic parameters on the authentication cost and latency are analyzed, respectively. Copyright © 2008 John Wiley & Sons, Ltd.

It is commonly recognized that today's Internet routing and addressing system is facing serious scaling problems, which are mainly caused by the overloading of IP address semantics. That is, an IP address represents not only the location but also the identity of a host. To address this problem, several recent schemes propose to replace the IP namespace in today's Internet with a locator namespace and an identity namespace. The locator namespace consists of locators that are used to represent the locations of hosts. On the other hand, the identity namespace consists of identifiers that are used to represent the identities of hosts. For these schemes to work, there must be a mapping system that can supply an appropriate locator for any given end point identifier (EID). While prior related works mainly focus on aggregable EIDs, several recent works proposed the use of self-certifying EIDs for purpose of security and privacy. However, self-certifying EIDs are flat, unstructured and prior proposals cannot be used to deal with flat EIDs. In this paper, we propose a Distributed hash table (DHT)-based identifier-to-locator mapping scheme to resolve a locator for a flat identifier. We evaluate the performance of the proposed scheme. We show that, besides the capability to support flat EIDs, the scheme has good scalability and low resolution delay. We also show that the scheme is robust and can efficiently support mobility.

Network mobility (NEMO) aims managing seamless connectivity for a group of mobile terminals as a whole mobile network. Multiple care of addresses (MCoA) registration scheme was also proposed to address seamless Internet connectivity issue. In this paper we first analyze the upload and download packet loss of mobile router (MR) in NEMO basic support protocol. Then the seamless Internet connectivity of MR which is equipped with WLAN, CDMA and GPRS interfaces is studied and experimented on our platform successfully. Finally, we analyze and compare the performance of packet loss ratio between uni-interfaced and multiple-interfaced MR, and results indicate that multiple interfaced MR can increase the performance of MR obviously when it moves across heterogenous overlay access networks.