Conference Paper

Traffic Split Scheme Based on Common Radio Resource Management in an Integrated LTE and HSDPA Networks

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Abstract

The future wireless communication networks will integrate different radio access technologies (RATs), which are referred to as heterogeneous wireless networks (HWNs). In this paper, we deal with two data oriented access networks, the Long Term Evolution (LTE) and the high speed downlink packet access (HSDPA). Assuming that the networks can support multi-homing access and the user can be served by both networks simultaneously, we propose a traffic split scheme with the aim of maximizing the throughput based on common radio resource management (CRRM). The split ratio in the scheme is dynamically adjusted under the consideration of the user's channel quality and the network load. The simulation results show that the proposed scheme can improve the throughput, also reduce the delay of the networks compared with the scheme using the fixed split ratio.

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... Recently, the coexistence of different wireless access network technologies has renewed this concept and became an attractive topic for study during the past years. Wireless networks multihoming concept started with offloading [31,32,33], passing by load balancing [34], optimal distribution [35] [36] [37], as well as concurrent multiple access [38,39,40]. ...
... For this aim, a reliable routing protocol must be considered [42]. Similarly, load balancing management could be obtained in heterogeneous wireless networks by dynamically optimizing the packets' split ratio between multiple access networks as shown in [34]. Such strategy might be based on the load information and channel quality information at each access network. ...
Thesis
Fifth generation mobile networks (5G) are being designed to introduce new services that require extreme broadband data rates and utlra-reliable latency. 5G will be a paradigm shift that includes heterogeneous networks with densification, virtualized radio access networks, mm-wave carrier frequencies, and very high device densities. However, unlike the previous generations, it will be a holistic network, tying any new 5G air interface and spectrum with the currently existing LTE and WiFi. In this context, we focus on new resource allocation strategies that are able to take advantage of multihoming in dual access settings. We model such algorithms at the flow level and analyze their performance in terms of flow throughput, system stability and fairness between different classes of users. We first focus on multihoming in LTE/WiFi heterogeneous networks. We consider network centric allocations where a central scheduler performs local and global proportional fairness (PF) allocations for different classes of users, single-homed and multihomed users. By comparison with a reference model without multihoming, we show that both strategies improve system performance and stability, at the expense of more complexity for the global PF. We also investigate user centric allocation strategies where multihomed users decide the split of a file using either peak rate maximization or network assisted strategy. We show that the latter strategy maximizes the average throughput in the whole network. We also show that network centric strategies achieve higher data rates than the user centric ones. Then, we focus on Virtual Radio Access Networks (V-RAN) and particularly on multi-resource allocation therein. We investigate the feasibility of virtualization without decreasing neither users performance, nor system's stability. We consider a 5G heterogeneous network composed of LTE and mm-wave cells in order to study how high frequency networks can increase system's capacity. We show that network virtualization is feasible without performance loss when using the dominant resource fairness strategy (DRF). We propose a two-phase allocation (TPA) strategy which achieves a higher fairness index than DRF and a higher system stability than PF. We also show significant gains brought by mm-wave instead of WiFi. Eventually, we consider energy efficiency and compare DRF and TPA strategies with a Dinklebach based energy efficient strategy. Our results show that the energy efficient strategy slightly outperforms DRF and TPA at low to medium load in terms of higher average throughput with comparable power consumption, while it outperforms them at high load in terms of power consumption. In this case of high load, DRF outperforms TPA and the energy efficient strategy in terms of average throughput. As for Jain's fairness index, TPA achieves the highest one
... This characteristic facilitates a seamless VHO process while it is seamless to the user[5]and allows the simultaneous transmission of multiple services across multiple network interfaces[6]. Several research projects use the multihoming strategy over a heterogeneous environment in order to achieve a load balancing[4];789or to make a better distribution of the bandwidth charge[10,11]. In other studies this strategy was used as a decision tool for the VHO process12131415. ...
... This characteristic facilitates a seamless VHO process while it is seamless to the user [5] and allows the simultaneous transmission of multiple services across multiple network interfaces [6]. Several research projects use the multihoming strategy over a heterogeneous environment in order to achieve a load balancing [4]; [7][8][9]or to make a better distribution of the bandwidth charge [10,11]. In other studies this strategy was used as a decision tool for the VHO process [12][13][14][15]. ...
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The telco operators face up to challenges related to the need of ensuring a quality of service to the user in a planning, maintenance and resource allocation in their complex networks. These challenges are directly related with the need to ensure an user’s service with a good level of quality in a highly dynamic environment in terms of changes in the radio access technologies, growth in the number of mobile users, technical requirements of the new services and applications, and the possibility to connect to different networks at the same time, among others. In this paper, we address the problem of the user’s service allocation into the different feasible networks in order to reduce the network overloading. We present a multihoming load balancing scheme that allows the re-allocation of services according to their QoS requirements and the availability of network resources. We propose a multi-objective optimization model of this problem together with an evolutionary algorithm to solve it. Through simulation in different scenarios, we show that our algorithm is efficient, sensitive, scalable and provides optimal solutions.
... The problem customizes the Lyapunov drift plus penalty optimization approach for achieving the desired output. Few other, traffic splitting solutions between Wi-Fi and cellular networks are discussed in [26,29,30], and few others on different networks like, [31] for LTE/HSPDA, [32] for Wi-Fi/UMTS, [33] for Wi-Fi/HSDPA. ...
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This work addresses the problem of traffic splitting for improving the overall delay jitter performance in the uplink multi-access system. We propose a packet-scheduling paradigm based on stochastic approximation algorithm to distribute the source traffic across the multiple network paths/interfaces. We first provide an analytical model and the delay jitter analysis for an individual interface. Later we formulate the traffic splitting problem as an optimization problem to learn the optimal split across the interfaces. We share the experimental results for the video and constant bit rate traffic on real networks (Wi-Fi or cellular networks) and convergence of our system using the proposed scheme in the dynamic network environment. The paradigm proposed in the paper is general and can be adapted to different objective functions.
... The load-balance is implemented in HetNet wireless networks by the dynamic optimization of the utility function of the split ratio of data among multiple access networks without considering the type of application or the needed quality of service QoS [14][15][16][17]. Up to the best of our knowledge, no work considered the possibility of data distribution by unequal load balance with multiple access simultaneously while considering the application type as a leading perspective. ...
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... We use AMC (Adaptive Modulation and Coding). This makes it possible to maintain a constant flow rate to the user regardless of his position and taking into account his mobility [29]. ...
... With the multi-homing service, a single stream of the media content should be split into multiple flows and assigned to different APs by the stream splitter. Therefore, it is important to control the flow rate r n,m for scheduling the flows and balancing the congestion across multiple APs [23]- [25]. Motivated from [26], we assume that MT m obtains reward U n,m (r n,m ) from AP n. ...
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... They showed that the combination of multihoming and network coding can improve significantly the service rate of Access Points (WiFi) and Base Stations (Cellular System) and reduce the system delay. An alternative technique based on traffic splitting using common radio resource management for Long Term Evolution (LTE) and High-Speed Downlink Packet Access (HSDPA) networks is presented in [12]. They propose a mathematical model to solve the traffic split problem. ...
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