Mobile Network Architecture Research Articles

Research and standards: advanced cloud and virtualization techniques for 5G networks (part II) [Guest Editorial

The evolution of mobile network architecture is an essential part in the development process of the fifth generation (5G) of cellular mobile systems, and that is through the incorporation of advanced cloud technologies and network function virtualization techniques. The new network architecture needs to support a wide range of high data rate applications and services, offering capacities of up to multiple gigabits per second, yet meeting extremely stringent latency and reliability requirements under a diverse variety of scenarios. Thus, the automation of network control and overall system management to achieve such an ambitious set of performance targets became crucial. Significant global effort for the necessary new technologies has been initiated.

Adaptive Compression and Joint Detection for Fronthaul Uplinks in Cloud Radio Access Networks

Cloud radio access network (C-RAN) has recently attracted much attention as a promising architecture for future mobile networks to sustain the exponential growth of data rate. In C-RAN, one data processing center or baseband unit (BBU) communicates with users via distributed remote radio heads (RRHs), which are connected to the BBU via high capacity, low latency fronthaul links. In this paper, we study the compression on fronthaul uplinks and propose a joint decompression algorithm at the BBU. The central premise behind the proposed algorithm is to exploit the correlation between RRHs. Our contribution is threefold. First, we propose a joint decompression and detection (JDD) algorithm which jointly performs decompressing and detecting. The JDD algorithm takes into consideration both the fading and compression effect in a single decoding step. Second, block error rate (BLER) of the proposed algorithm is analyzed in closed-form by using pair-wise error probability analysis. Third, based on the analyzed BLER, we propose adaptive compression schemes subject to quality of service (QoS) constraints to minimize the fronthaul transmission rate while satisfying the pre-defined target QoS. As a dual problem, we also propose a scheme to minimize the signal distortion subject to fronthaul rate constraint. Numerical results demonstrate that the proposed adaptive compression schemes can achieve a compression ratio of 300% in experimental setups.

Role of Mobile Agents in the Layered Architecture of Mobile Ad-hoc Networks

In today's world mobile agents and mobile ad- hoc networks are the two technologies that are contributing towards better connectivity and communicability. When the two technologies used jointly, the interest is increased. Due to the properties like self- configuration and infrastructure-less, the mobile ad-hoc networks provide various remarkable features. But the various challenges are also associated with mobile ad-hoc networks like dynamic topology, mobility, energy constraint etc. Mobile agent provides solution to these challenges. A mobile agent is a new way of computer interactions and provides better options for the developers to create applications based on connectivity. Mobile agents move around the ad-hoc networks in a different and better way than the other widespread client server architecture based applications. Due to their mobility and autonomy these agents can perform various functions in mobile ad-hoc networks like topology discovery, routing, key management, congestion control etc. The paper reviews the role of the mobile agents in the mobile ad-hoc networks, and emphasizes its application on the various layers of a layered architecture of mobile ad-hoc networks and concludes its merits as compared to other conventional approaches.

Future railway services-oriented mobile communications network

The future development of the railway is highly desired to evolve into a new era where infrastructure, trains, travelers, and goods will be increasingly interconnected to provide high comfort, with optimized door-to-door mobility at higher safety. For this vision, it is required to realize seamless high data rate wireless connectivity for railways. To improve the safety and comfort of future railways, wireless communications for railways are required to evolve from only voice and traditional train control signaling services to various high data rate services including critical high-definition (HD) video and other more bandwidth-intensive passenger services, such as onboard and wayside HD video surveillance, onboard real-time high data rate services, train multimedia dispatching video streaming, railway mobile ticketing, and the Internet of Things for railways. Corresponding mobile communications network architecture under various railway scenarios including inter-car, intra-car, inside station, train-to-infrastructure and infrastructure- to-infrastructure are proposed in this article. Wireless coverage based on massive MIMO for railway stations and train cars is proposed to fulfill the requirement of high-data-rate and high spectrum efficiency. The technical challenges brought by the massive MIMO technique are discussed as well.

QoE-Based SVC Layer Dropping in LTE Networks Using Content-Aware Layer Priorities

The increasing popularity of mobile video streaming applications has led to a high volume of video traffic in mobile networks. As the base station, for instance, the eNB in LTE networks, has limited physical resources, it can be overloaded by this traffic. This problem can be addressed by using Scalable Video Coding (SVC), which allows the eNB to drop layers of the video streams to dynamically adapt the bitrate. The impact of bitrate adaptation on the Quality of Experience (QoE) for the users depends on the content characteristics of videos. As the current mobile network architectures do not support the eNB in obtaining video content information, QoE optimization schemes with explicit signaling of content information have been proposed. These schemes, however, require the eNB or a specific optimization module to process the video content on the fly in order to extract the required information. This increases the computation and signaling overhead significantly, raising the OPEX for mobile operators. To address this issue, in this article, a content-aware (CA) priority marking and layer dropping scheme is proposed. The CA priority indicates a transmission order for the layers of all transmitted videos across all users, resulting from a comparison of their utility versus rate characteristics. The CA priority values can be determined at the P-GW on the fly, allowing mobile operators to control the priority marking process. Alternatively, they can be determined offline at the video servers, avoiding real-time computation in the core network. The eNB can perform content-aware SVC layer dropping using only the priority values. No additional content processing is required. The proposed scheme is lightweight both in terms of architecture and computation. The improvement in QoE is substantial and very close to the performance obtained with the computation and signaling-intensive QoE optimization schemes.

SDN and Virtualization-Based LTE Mobile Network Architectures: A Comprehensive Survey

Software-defined networking (SDN) features the decoupling of the control plane and data plane, a programmable network and virtualization, which enables network infrastructure sharing and the softwarization of the network functions. Recently, many research works have tried to redesign the traditional mobile network using two of these concepts in order to deal with the challenges faced by mobile operators, such as the rapid growth of mobile traffic and new services. In this paper, we first provide an overview of SDN, network virtualization, and network function virtualization, and then describe the current LTE mobile network architecture as well as its challenges and issues. By analyzing and categorizing a wide range of the latest research works on SDN and virtualization in LTE mobile networks, we present a general architecture for SDN and virtualization in mobile networks (called SDVMN) and then propose a hierarchical taxonomy based on the different levels of the carrier network. We also present an in-depth analysis about changes related to protocol operation and architecture when adopting SDN and virtualization in mobile networks. In addition, we list specific use cases and applications that benefit from SDVMN. Last but not least, we discuss the open issues and future research directions of SDVMN.

An Agent based Intrusion Detection System Architecture for Mobile Ad Hoc Networks using Ant Colony Algorithm

An Agent based Intrusion Detection System Architecture for Mobile Ad Hoc Networks using Ant Colony Algorithm

An openflow architecture for energy-aware traffic engineering in mobile networks

To cope with the growing traffic demand, future mobile networks will be denser and integrate heterogeneous technologies. However, if not properly engineered, such networks may incur huge energy waste when there is little traffic, and may suffer from an unbearable management burden caused by the variety of technologies integrated. In this article, we propose and implement a novel management architecture for mobile networks based on OpenFlow, which supports resource-ondemand provisioning in a centralized control plane, and hides the technology specifics from the controller through the use of abstractions. The feasibility of the approach is demonstrated by a real-life prototype based on commercial off-the-shelf devices.

Proposal and evaluation of SDN‐based mobile packet core networks

Recently, several researchers have proposed adopting software‐defined networking (SDN) concepts for mobile network architectures, particularly for LTE‐evolved packet core (LTE/EPC). Although several new designs have been introduced for architectures based on SDN or its concrete realization, Openflow, few studies have presented in‐depth discussions of real procedures that are relevant to such architectures. To this end, this paper first surveys the current approaches and solutions for adopting SDN/Openflow in LTE/EPC architectures and then introduces a new Openflow‐enabled EPC (OEPC) architecture. This work provides detailed analyses of five procedures that commonly occur in LTE/EPC architectures, and the analyses are further elaborated with the separation of the control and data planes and the support of extended Openflow protocol. The analysis shows that the data management of these procedures is simpler relative to traditional LTE/EPC. In addition, in order to prove that efficient data management takes place for these procedures relative to a traditional LTE/EPC architecture, the numbers of signalling messages that are processed by control entities (i.e., the MME and the controller) are taken into account as a metric to evaluate the OEPC architecture. Moreover, the results of a numerical evaluation also show the benefits of this proposal relative to another Openflow‐based LTE/EPC architecture.

Cellular software defined networking: a framework

Today's mobile customers desire to remain connected anywhere, at any time, and using any device. This phenomenon has encouraged mobile network operators to build complex network architectures by incorporating new features and extensions, which are harder to manage and operate. In this article we propose a novel and simplified architecture for mobile networks. The proposed architecture, which we call CSDN (Cellular SDN), leverages software defined networking (SDN) and network functions virtualization (NFV). SDN abstracts the network and separates the control plane from the data plane; NFV decouples logical network functions from the underlying hardware, for dynamic resource orchestration. Furthermore, we argue that dynamic resource orchestration and optimal control need real-time context data analyses to make intelligent decisions. Thus, in the proposed architecture we exploit the capability of the mobile edge networks to gather information related to the network as well as the users. This information can be used to optimize network utilization and application performance, and to enhance the user experience. In addition, the gathered data can be shared with third party service providers, enabling the realization of innovative services.

Research & standards: advanced cloud & virtualization techniques for 5G networks [Guest Editorial

The evolution of mobile network architecture is an essential part in the development process of the fifth generation (5G) of cellular mobile systems, and that is through the incorporation of advanced cloud technologies and network function virtualization techniques. The new network architecture needs to support a wide range of high data rate applications and services, offering capacities of up to multiple gigabits per second, yet meeting extremely stringent latency and reliability requirements under a diverse variety of scenarios. Thus the automation of network control and overall system management to achieve such an ambitious set of performance targets became crucial. Significant global effort for the necessary new technologies has been initiated.

I-Net: new network architecture for 5G networks

In order to deal with the challenges and opportunities presented by the mobile Internet, this paper proposes a new Internet-oriented mobile network architecture, dubbed i-Net, for fifth generation (5G) mobile communication systems. Based on direct communications established between the base stations (BSs), i-Net can implement local data routing for mobile data traffic, which adapts to increased service localization for the mobile Internet. We first present the network architecture and main technical features, i.e., inter-connection, integration, and intelligence. Then the key techniques are discussed to show their potential in improving the network efficiency of i-Net. Field trials for inter-BS direct communications to implement cooperative multipoint oPeration (CoMP) in i-Net are carried out to demonstrate the feasibility of i-Net. It is expected that i-Net can provide a good quality of experience for end users through the efficient integration of the multi-BS, multi-band, and multi-radio-access-technology (RAT) radio resources in 5G.

Device-to-device-based heterogeneous radio access network architecture for mobile cloud computing

The emerging heterogeneous mobile network architecture is designed for an increasing amount of traffic, quality requirements, and new mobile cloud computing demands. This article proposes a hierarchical cloud computing architecture to enhance performance by adding a mobile dynamic cloud formed by powerful mobile devices to a traditional general static cloud. A mobile dynamic cloud is based on heterogeneous wireless architecture where device-to-device communication is used for data transmission between user devices. The main advantage of the proposed architecture is an increase in overall capacity of a mobile network through improved channel utilization and traffic offloading from Long Term Evolution-Advanced to device-to-device communication links. Simulations show that the proposed architecture increases the capacity of a mobile network by up to 10 percent depending on the conditions and amount of offloaded data. The offloading probability is also evaluated by taking into consideration the number of devices in the cloudlet and the content matching values. We have gained insight into how content similarity affects offloading probability much more than the number of devices in a cloudlet.

Integrating network function virtualization with SDR and SDN for 4G/5G networks

The rapidly diversified market demands have presented a huge challenge to the conventional mobile broadband network architecture. On one hand, the limited machine room space and insufficient power supply make it impossible to accommodate exponentially growing amount of network equipment of operators. On the other hand, net heterogeneity caused by different specifications of wireless access equipment causes costly trouble related to management and optimization. This article, correspondingly, proposes a holistic solution involving different technologies, i.e. network function virtualization (NFV), software defined radio (SDR), and software defined network (SDN). In particular, we investigate both existing standards and possible extensions for 4G/5G mobile networks, followed by a few open issues for future research.

Distributed mobility management for future 5G networks: overview and analysis of existing approaches

The ever-increasing demand of mobile Internet traffic is pushing operators to look for solutions to increase the available bandwidth per user and per unit of area. At the same time, they need to reduce the load in the core network at a reasonable cost in their future 5G deployments. Today's trend points to the deployment of extremely dense networks in order to provide ubiquitous connectivity at high data rates. However, this is hard to couple with the current mobile networks' architecture, which is heavily centralized, posing difficult challenges when coping with the foreseen explosion of mobile data. Additionally, future 5G networks will exhibit disparate types of services, posing different connectivity requirements. Distributed mobility management is emerging as a valid framework to design future mobile network architectures, taking into account the requirements for large traffic in the core and the rise of extremely dense wireless access networks. In this article, we discuss the adoption of a distributed mobility management approach for mobile networks, and analyze the operation of the main existing solutions proposed so far, including a first practical evaluation based on experiments with real Linux-based prototype implementations.

Developing Standards, Shaping the Network: Ethnographic Notes on the IEEE 802 LAN/MAN Standards Committee

This paper will address the very technopolitical nature of standards development activity based upon the ethnographic research realized by the author at the IEEE Standards Board (SASB) series of meetings, and at the IEEE 802 LAN/MAN Standards Committee (LMSC) meetings. For our purposes, standards can be defined as agreed-upon rules, protocols, or technical specifications that assure interoperability. The paper is organized in two main sections: the first one is a descriptive experiment in which the reader will be introduced to the IEEE-SA and, more narrowly, to the 802 LMSC. Then, in the second main session, we will explore the entanglements between three reality domains comprised by the standardization process: technical problem-solving activity, business strategy and technology governance. The main goal is to address contemporary technopolitical dilemmas in regard to the mobile broadband network evolution, including the convergence process between wireless (WLAN) and mobile (cellular) network architectures.

FLIP: enforcing IP mobility to the cellular network edge

The mobile network core is evolving towards an unlayered and decentralised architecture, in which the current centralised mobility management mechanisms cannot be used efficiently. In this paper, a flat IP FLIP mobility management approach is proposed. It enforces IP mobility to the cellular network edge with the help of the distributed gateways. In FLIP, mobility management-related information is maintained in the distributed gateways, and multiple management domains tailored for cellular networks are considered. Autonomicity is also integrated in FLIP. Besides, FLIP supports also the ID/locator separation and the smooth transition between the upgraded mobile hosts and the traditional hosts. A prototype of FLIP has been implemented and an experimental network consisting of commercial and educational network has been established. Experimental and evaluation results show that FLIP is an efficient approach for mobility management oriented to the future mobile network architecture.

Toward Elastic Distributed SDN/NFV Controller for 5G Mobile Cloud Management Systems

Future 5G mobile network architecture is expected to offer capacities to accommodate the inexorable rise in mobile data traffic and to meet further stringent latency and reliability requirements to support diverse high data rate applications and services. Mobile cloud computing (MCC) in 5G has emerged as a key paradigm, promising to augment the capability of mobile devices through provisioning of computational resources on demand, and enabling resource-constrained mobile devices to offload their processing and storage requirements to the cloud infrastructure. Follow-me cloud (FMC), in turn, has emerged as a concept that allows seamless migration of services according to the corresponding users mobility. Meanwhile, software-defined networking (SDN) is a new paradigm that permits the decoupling of the control and data planes of traditional networks and provides programmability and flexibility, allowing the network to dynamically adapt to change traffic patterns and user demands. While the SDN implementations are gaining momentum, the control plane is still suffering from scalability and performance concerns for a very large network. In this paper, we address these scalability and performance issues in the context of 5G mobile networks by introducing a novel SDN/OpenFlow-based architecture and control plane framework tailored for MCC-based systems and more specifically for FMC-based systems where mobile nodes and network services are subject to constraints of movements and migrations. Contrary to a centralized approach with a single SDN controller, our approach permits the distribution of the SDN/OpenFlow control plane on a two-level hierarchical architecture: a first level with a Global FMC Controller (G-FMCC), and a second level with several Local FMC Controllers (L-FMCCs). Thanks to our control plane framework and Network Function Virtualization (NFV) concept, the L-FMCCs are deployed on-demand, where and when needed, depending on the global system load. Results obtained via analysis show that our solution ensures more efficient management of control plane, performance maintaining, and network resources preservation.

VirFID: A Virtual Force (VF)-based Interest-Driven moving phenomenon monitoring scheme using multiple mobile sensor nodes

In this paper, we study mobile sensor network (MSN) architectures and algorithms for monitoring a moving phenomenon in an unknown and open area using a group of autonomous mobile sensor (MS) nodes. Monitoring a moving phenomenon involves challenges due to limited communication/sensing ranges of MS nodes, the phenomenon’s unpredictable changes in distribution and position, and the lack of information on the sensing area. To address the challenges and meet the objective of the maximization of weighted sensing coverage, we propose a novel scheme, namely VirFID (Virtual Force (VF)-based Interest-Driven moving phenomenon monitoring). In VirFID, MS nodes move toward the positions where more interesting sensing data can be obtained by utilizing the virtual force, which is calculated based on the distance between MS nodes and sensed values in the area of interest. MS nodes also perform network-wise information sharing to increase the weighted sensing coverage. Depending on the level of information used, three variants of VirFID are evaluated: VirFID-LIB (Local Information-Based), VirFID-GHL (Global Highest and Lowest), and VirFID-IBN (Interests at Boundary Nodes). In addition, an analytical model for estimating MSN speed is designed. Simulations are performed to compare the performance of three VirFID variants with other approaches. Our simulation results show that VirFID algorithms outperform other schemes in terms of the weighted coverage efficiency, and VirFID-IBN achieves the highest weighted coverage efficiency among VirFID variants.

Terminal-centric distribution and orchestration of IP mobility for 5G networks

Advances in radio access technologies and mobile terminals are fueling the growth of Internet traffic via mobile networks. The upcoming 5G era, with a new 5G radio technology and increased utilization of heterogeneous networking, will further accelerate mobile data usage. One of the pillars of mobile network architecture is IP mobility management, which is currently based on centralized data path management. In this article, we first describe the efficiency issues of the centralized approach. We then discuss multiple dimensions of distributing the mobility functions, and suggest how the mobile terminal can utilize them in orchestration for efficient communication over a 5G flat mobile network.