Evolved Universal Terrestrial Radio Access Network Research Articles

Performance Evaluation of LTE Network using Maximum Flow Algorithm

In this paper, we propose a new traffic flow model of the Long Term Evaluation (LTE) network for the Evolved Universal Terrestrial Radio Access Network (E-UTRAN). Here only one Evolve Node B (eNB) nearest to the Mobility Management Entity (MME) and Serving Gateway (S-GW) will use the S1 link to bridge the E-UTRAN and Evolved Packet Core (EPC). All the eNBs of a tracking area will be connected to each other by the X2 link. Determination of capacity of a links of such a network is a challenging job since each node offers its own traffic and at the same time conveys traffic of other nodes. In this paper, we apply maximum flow algorithm including superposition theorem to solve the traffic flow of radio network. Using the total flow per subcarrier, a new traffic model is also developed in the paper. The relation among the traffic parameters: ‘blocking probability’, ‘offered traffic’, ‘instantaneous capacity’, ‘average holding time’, and ‘number of users’ are shown graphically under both QPSK and 16-QAM. The concept of the network will be helpful to improve the SINR of the received signal ofeNBslocated long distance relative to MME/S-GW.

A Comparison of Voice-over-IP Capacity and Performance for Different Scheduling Techniques

To ensure Quality of Service (QoS), different scheduling techniques play a very vital role for Voice over IP (VoIP) traffic. The traffic for VoIP service is constant bit traffic and has low latency, which implies that small VoIP packets are imparted in the typical duration of time. Also, for QoS related to packet delay and packet loss, the Voice over IP packet needs to be anticipated periodically. Dynamic scheduling is used for packet scheduling in the Evolved UTRAN (E-UTRAN) type of radio systems. In present work, we will compare different type of scheduling techniques such as dynamic scheduling, persistent scheduling, and semi-persistent (with SID packets) scheduling used for VoIP packets in Long Term Evolution (LTE). We try to find out the number of users supported for different Control Channels (CC) with and without restrictions. The results show that semi-persistent scheduling is the most efficient scheduling as it helps in better-optimized resource utilization while dynamic scheduling has a large amount of signaling involved which reduces its efficiency. Persistent scheduling technique fails to utilize the resource as compared to semi-persistent scheduling. VoIP capacity related to the number of users is calculated for Semi-persistent Scheduling without any condition on control channels and as a result, we observed some prominent data.

An Optimal Security Management Framework for Backhaul-aware 5G-Vehicle to Everything (V2X)

Cellular (C) setups facilitate the connectivity amongst the devices with better provisioning of services to its users. Vehicular networks are one of the representative setups that aim at expanding their functionalities by using the available cellular systems like Long Term Evolution (LTE)-based Evolved Universal Terrestrial Radio Access Network (E-UTRAN) as well as the upcoming Fifth Generation (5G)-based functional architecture. The vehicular networks include Vehicle to Vehicle (V2V), Vehicle to Infrastructure (V2I), Vehicle to Pedestrian (V2P) and Vehicle to Network (V2N), all of which are referred to as Vehicle to Everything (V2X). 5G has dominated the vehicular network and most of the upcoming research is motivated towards the fully functional utilization of 5G-V2X. Despite that, credential management and edge-initiated security are yet to be resolved under 5G-V2X. To further understand the issue, this paper presents security management as a principle of sustainability and key-management. The performance tradeoff is evaluated with the key-updates required to maintain a secure connection between the vehicles and the 5G-terminals. The proposed approach aims at the utilization of high-speed mmWave-based backhaul for enhancing the security operations between the core and the sub-divided functions at the edge of the network through a dual security management framework. The evaluations are conducted using numerical simulations, which help to understand the impact on the sustainability of connections as well as identification of the fail-safe points for secure and fast operations. Furthermore, the evaluations help to follow the multiple tradeoffs of security and performance based on the metrics like mandatory key updates, the range of operations and the probability of connectivity.

UPPGHA: Uniform Privacy Preservation Group Handover Authentication Mechanism for mMTC in LTE-A Networks

Machine Type Communication (MTC), as one of the most important wireless communication technologies in the future wireless communication, has become the new business growth point of mobile communication network. It is a key point to achieve seamless handovers within Evolved-Universal Terrestrial Radio Access Network (E-UTRAN) for massive MTC (mMTC) devices in order to support mobility in the Long Term Evolution-Advanced (LTE-A) networks. When mMTC devices simultaneously roam from a base station to a new base station, the current handover mechanisms suggested by the Third-Generation Partnership Project (3GPP) require several handover signaling interactions, which could cause the signaling load over the access network and the core network. Besides, several distinct handover procedures are proposed for different mobility scenarios, which will increase the system complexity. In this paper, we propose a simple and secure uniform group-based handover authentication scheme for mMTC devices based on the multisignature and aggregate message authentication code (AMAC) techniques, which is to fit in with all of the mobility scenarios in the LTE-A networks. Compared with the current 3GPP standards, our scheme can achieve a simple authentication process with robust security protection including privacy preservation and thus avoid signaling congestion. The correctness of the proposed group handover authentication protocol is formally proved in the Canetti-Krawczyk (CK) model and verified based on the AVISPA and SPAN.

Real Time- Optimized Scheduler Using Earliest Due Date Mechanism in LTE Downlink System

Long Term Evolution (LTE) is standardized by the Third Generation Partnership Project (3GPP) as the most recent standard in the mobile network technology tree with flat architecture in order to conduct a new model aiming to offer higher-data-rate, lower-latency, and packet-optimized radio access technology called Evolved Universal Terrestrial Radio Access Network (E-UTRAN). However, the schedulers aiming to deal with the Real Time (RT) and the Non-Real Time (NRT) traffic have not defined by the 3GPP specifications. Accordingly, it is very important to design and implement optimum scheduling schemes for achieving the required Quality of Service (QoS) prerequisites such as packet delay and Packet Loss Rate (PLR) of RT multimedia services in E-UTRAN. Thus, the proposed scheduler is presented in this paper as well as the performance of the new scheduling strategy which is based on the Earliest Due Date (EDD) approach. The new proposed scheduler provides better results as compared with the conventional scheduling strategies, especially for multimedia applications in downlink framework of LTE system. The proposed scheduler achieves the highest good-put as well as the lowest PLR especially for the video users.

An Uniform Handover Authentication between E-UTRAN and Non-3GPP Access Networks

To achieve seamless handovers between the Evolved Universal Terrestrial Radio Access Network (E-UTRAN) and other access networks is a challenging task as it requires comprehensive real-time interconnectivity in the LTE networks. The third Generation Partnership Project (3GPP) has suggested support the mobility between the E-UTRAN and non-3GPP access networks, which requires full access authentication procedures and distinct procedures for different mobility scenarios, which will bring a lot of message exchanges and increase the system complexity. Besides, the existing handover schemes for other wireless networks are not suitable for the mobility scenarios in the LTE networks due to their inherent vulnerabilities. In this paper, we propose a fast and secure handover authentication scheme to fit in with all of the mobility scenarios in the LTE networks. Compared with other handover schemes, our scheme cannot only provide strong security guarantees including Perfect Forward Secrecy (PFS) and Master Key Forward Secrecy (MKFS) and user anonymity, but also achieve a simple authentication process with robust efficiency in terms of communication cost, storage cost and computational cost. The experimental results and formal verification by using the TLA+ and TLC show that the proposed scheme is secure against various malicious attacks.

Efficient Control Channel Resource Allocation for VoIP in OFDMA-Based Packet Radio Networks

We propose an efficient control channel resource allocation approach to enhance the performance of voice-over-IP (VoIP) in orthogonal frequency division multiple access- (OFDMA-) based next generation mobile communication systems. As the long-term evolution (LTE) of universal terrestrial radio access network (UTRAN), evolved UTRAN (E-UTRAN) is the first OFDMA-based packet radio network and thus selected in this paper as an application example. Our proposed physical downlink control channel (PDCCH) resource allocation approach for E-UTRAN is composed of bidirectional power control, inner loop link adaptation (ILLA), and outer loop link adaptation (OLLA) algorithms. Its effectiveness is validated through large-scale radio system level simulations, and simulation results confirm that VoIP capacity with dynamic scheduling can be further enhanced with this PDCCH resource allocation approach. Moreover, the VoIP performance requirements for international mobile telecommunications-advanced (IMT-Advanced) radio interface technologies can be met with dynamic scheduling together with proposed PDCCH resource allocation. Besides E-UTRAN, this approach can be introduced to other OFDMA-based mobile communication systems for VoIP performance enhancement as well.

Enhancing VoIP in UTRAN LTE Downlink: Methods and Performance

In this article, we study different methods to enhance the capacity of Voice-over-IP (VoIP) in Evolved UTRAN (E-UTRAN) downlink. According to previous E-UTRAN system level simulation results, VoIP capacity with dynamic scheduling and semi-persistent scheduling is limited by available Physical Downlink Control CHannel (PDCCH) resources and Physical Downlink Shared CHannel (PDSCH) resources respectively. The different behavior of these two packet scheduling schemes and specific bottleneck on capacity lead us to formulate two distinctly different performance enhancement strategies, which are the main focus of this paper. For dynamic scheduling, we propose a bi-directional power control algorithm to rationalize PDCCH resource allocation, thus greatly improving VoIP capacity. For semi-persistent scheduling, we introduce Adaptive Transmission Bandwidth (ATB) to rationalize PDSCH resource allocation and further apply dynamic packet bundling in highly-loaded network, thus improving VoIP capacity in a considerable manner. The proposed enhancement methods are validated through large-scale system level simulations and the obtained system simulation results further confirm effectiveness of these enhancement methods.

Performance study for HARQ–ARQ interaction of LTE

AbstractThe 3GPP working group proposes the Long‐Term Evolution (LTE) system as the 4G mobile communications technology. To reduce the transmission latency in the radio access network, Evolved Universal Terrestrial Radio Access Network (E‐UTRAN), of LTE, the base station and radio network controller are merged into a single network node, namely eNB. In E‐UTRAN, the Stop‐And‐Wait Hybrid ARQ (SAW‐HARQ) protocol in the Media Access Control (MAC) layer deals with transmission errors without the need to engage the ARQ protocol in the Radio Link Control (RLC) layer. The HARQ and ARQ protocols interact only in case of dealing HARQ residual errors. In this paper, we propose an analytical model to model the behavior of the HARQ–ARQ Interaction. Our analytical model is validated against the simulation experiments that provide more performance metrics (which cannot be obtained through our analytical model). Finally, we investigate the impacts of the HARQ–ARQ Interaction on the Protocol Data Unit (PDU) transmission delay based on our simulation experiments. Copyright © 2009 John Wiley & Sons, Ltd.