QoS Profiles Research Articles

Quantifying the Density of mmWave NR Deployments for Provisioning Multi-Layer VR Services

The 5G New Radio (NR) technology operating in millimeter wave (mmWave) frequency band is designed for support bandwidth-greedy applications requiring extraordinary rates at the access interface. However, the use of directional antenna radiation patterns, as well as extremely large path losses and blockage phenomenon, requires efficient algorithms to support these services. In this study, we consider the multi-layer virtual reality (VR) service that utilizes multicast capabilities for baseline layer and unicast transmissions for delivering an enhanced experience. By utilizing the tools of stochastic geometry and queuing theory we develop a simple algorithm allowing to estimate the deployment density of mmWave NR base stations (BS) supporting prescribed delivery guarantees. Our numerical results show that the highest gains of utilizing multicast service for distributing base layer is observed for high UE densities. Despite of its simplicity, the proposed multicast group formation scheme operates close to the state-of-the-art algorithms utilizing the widest beams with longest coverage distance in approximately 50–70% of cases when UE density is λ≥0.3. Among other parameters, QoS profile and UE density have a profound impact on the required density of NR BSs while the effect of blockers density is non-linear having the greatest impact on strict QoS profiles. Depending on the system and service parameters the required density of NR BSs may vary in the range of 20–250 BS/km2.

DDS middleware on top of FlexRay networks: Simulink blockset implementation of electrical vehicle using FlexRay protocol and its adaptation to DDS concept

We designed a Simulink vehicle blockset in order to integrate safety, reliability, best condition of luxury and comfort in modern models by adding or modifying some old algorithms, implemented as application layer components. The proposed blockset corresponds to the Society of Automotive Engineers benchmark which is normally connected by the CAN bus that we replaced by the FlexRay bus. We used the Embedded MATLAB tool for implementing this blockset in order to generate a portable C standard code. To connect the designed sub-blocks together, we applied the real-time middleware data distribution service (DDS) and the FlexRay protocol. In this paper, we focused our interest on the implementation of the Simulink blockset with its different sub-blocks and we then identified their DDS entities and their QoS profiles. We also calculated the worst-case response time, based on the full scheduling model, which served to configure the DDS deadline QoS and the FlexRay protocol parameters.

A specification-based QoS-aware design framework for service-based applications

Effective and accurate service discovery and composition rely on complete specifications of service behaviour, containing inputs and preconditions that are required before service execution, outputs, effects and ramifications of a successful execution and explanations for unsuccessful executions. The previously defined Web Service Specification Language (WSSL) relies on the fluent calculus formalism to produce such rich specifications for atomic and composite services. In this work, we propose further extensions that focus on the specification of QoS profiles, as well as partially observable service states. Additionally, a design framework for service-based applications is implemented based on WSSL, advancing state of the art by being the first service framework to simultaneously provide several desirable capabilities, such as supporting ramifications and partial observability, as well as non-determinism in composition schemas using heuristic encodings; providing explanations for unexpected behaviour; and QoS-awareness through goal-based techniques. These capabilities are illustrated through a comparative evaluation against prominent state-of-the-art approaches based on a typical SBA design scenario.

5G-Crosshaul: An SDN/NFV Integrated Fronthaul/Backhaul Transport Network Architecture

This article proposes an innovative architecture design for a 5G transport solution (dubbed 5G-Crosshaul) targeting the integration of existing and new fronthaul and backhaul technologies and interfaces. At the heart of the proposed design lie an SDN/NFV-based management and orchestration entity (XCI), and an Ethernet-based packet forwarding entity (XFE) supporting various fronthaul and backhaul traffic QoS profiles. The XCI leverages widespread architectural frameworks for NFV (ETSI NFV) and SDN (Open Daylight and ONOS). It opens the 5G transport network as a service for innovative network applications on top (e.g., multi-tenancy, resource management), provisioning the required network and IT resources in a flexible, cost-effective, and abstract manner. The proposed design supports the concept of network slicing pushed by the industry for realizing a truly flexible, sharable, and cost-effective future 5G system.

A Multi-Service Oriented Multiple Access Scheme for M2M Support in Future LTE

We propose a novel multiple access technique to overcome the shortcomings of the current proposals for the future releases of LTE. We provide a unified radio access system that efficiently and flexibly integrates both traditional cellular services and M2M connections arising from IoT applications. The proposed solution, referred to as MOMA, is based on establishing separate classes of users using relevant criteria that go beyond the simple handheld-IoT device split; service-dependent hierarchical spreading of the data signals; and a mix of multiuser and single-user detection schemes at the receiver. Signal spreading in MOMA allows densely connected devices with different QoS profiles to be handled, and at the same time its flexible receiver structure allows the receiver computational resources to be allocated to the connections that need them most. This yields scalable and efficient use of the available radio resources and better service integration. While providing significant advantages for key future communications scenarios, MOMA can be incorporated into LTE with a limited impact on the protocol structure and the signaling overhead.

QoS Aware load balance in software defined LTE networks

Exponential growth of mobile subscribers and various application data traffic requirements cause exorbitant load in Long Term Evolution (LTE) networks. Telecom operators are considering small cells and Wi-Fi for handling this huge traffic demand. As User Equipments (UEs) are typically associated with a near-by cell (eNB), spatio-temporal variation in traffic demands makes the LTE networks suffer from load imbalance problem. Due to the distributed nature of eNB operation in LTE Radio Access Network (RAN), traditional solutions to tackle load imbalance problem could lead to excessive overhead over X2 interface. Hence, managing densely deployed cells is very challenging in the existing distributed LTE RAN. In this work, load imbalance issue is addressed by proposing a centralized Software Defined LTE RAN (SD-LTE-RAN) framework and a novel QoS Aware Load Balance (QALB) algorithm. For taking load balance decisions, the QALB algorithm considers loads of neighbor cells, QoS profiles of UEs and their expected throughputs w.r.t. neighbor cells. Unlike existing load balance algorithms, it does not change handover-offset parameters of cells to avoid ping pong handovers. The proposed framework and QALB algorithm are implemented in NS-3 simulator. In various load balance scenarios, proposed QALB algorithm is able to maintain better QoS data rates (> 80% of their configured Guaranteed Bit Rates (GBRs)) for more than 70% of the cells in the network. While existing load balance algorithms are able to do the same for only 50% of the cells in the network. In overall, the QALB algorithm is able to decrease the total network overload by 15% compared to existing load balance algorithms. We also evaluated the QALB algorithm in mobility scenarios and identified that it is able to decrease average network overload by 10% compared to existing load balance algorithms. To evaluate the network wide fair load distribution, we defined load balance index (LBI) using Jain’s Fairness Index.

System level performance of IEEE 802.22-2011 with sensing-based detection of wireless microphones

We present the state-of-the-art system level evaluation of the IEEE 802.22-2011 standard using a highly detailed simulator implementation in NS-2. In the evaluation our attention is focused on the effect of spatiotemporal wireless microphone (WM) activity on the performance of the IEEE 802.22-2011 network, while considering novel spectrum sensing strategies and multimedia traffic with different prioritization in IEEE 802.22-2011. Our general finding is that the IEEE 802.22-2011 standard deals well with WMs and prioritization of simultaneous multimedia traffic using different QoS profiles, while some surprising conclusions follow.

Radio resource allocation algorithms for multi-service OFDMA networks: the uniform power loading scenario

Adaptive Radio Resource Allocation is essential for guaranteeing high bandwidth and power utilization as well as satisfying heterogeneous Quality-of-Service requests regarding next generation broadband multicarrier wireless access networks like LTE and Mobile WiMAX. A downlink OFDMA single-cell scenario is considered where heterogeneous Constant-Bit-Rate and Best-Effort QoS profiles coexist and the power is uniformly spread over the system bandwidth utilizing a Uniform Power Loading (UPL) scenario. We express this particular QoS provision scenario in mathematical terms, as a variation of the well-known generalized assignment problem answered in the combinatorial optimization field. Based on this concept, we propose two heuristic search algorithms for dynamically allocating subchannels to the competing QoS classes and users which are executed under polynomially-bounded cost. We also propose an Integer Linear Programming model for optimally solving and acquiring a performance upper bound for the same problem at reasonable yet high execution times. Through extensive simulation results we show that the proposed algorithms exhibit high close-to-optimal performance, thus comprising attractive candidates for implementation in modern OFDMA-based systems.

Bertrand–Edgeworth pricing equilibrium in Web service markets

PricingWebserviceswithdifferentQualityofService(QoS)classesovertheInternetisachallengingscientificproblem. Finding the optimal price per QoS class allows each provider to maximize its revenue and to solve the capacity planning problem. The most works presented in the literature focus on a monopolistic setting where one service provider sells one or more services of different classes to a number of customers. The Service Level Agreement (SLA) is the most commonly used contract scheme, whereby providers announce their QoS profiles specifying a number of QoS classes and the related prices. The most results available in the literature to find the optimal QoS profile of a provider do not take into account the QoS profiles announced by other providers. However, in real-world settings, services sale competition among service providers is common and cannot be neglected. In this paper, we design a game-theoretical model for Web service markets with a single service characterized by response time and price by extending the Bertrand-Edgeworth's oligopoly, and we provide a polynomial-time algorithm to find a Nash equilibrium with two providers and an arbitrary number of customers.

Control-level call differentiation in IMS-based 3G core networks

The 3GPP-defined IP Multimedia Subsystem is becoming the de facto standard for IP-based multimedia communication services. It consists of an overlay control and service layer that is deployed on top of IP-based mobile and fixed networks, in order to enable the seamless provisioning of IP multimedia services to 3G users. Service differentiation, which implies the network's ability to distinguish between different classes of traffic (or service) and provide each class with the appropriate treatment, is an important aspect that is considered in 3G networks. In this article, we present a critical review of existing service differentiation solutions and propose a new control-level call differentiation solution for IMS-based 3G core networks. The solution consists of a novel call differentiation scheme, enabling the definition of various categories of calls with different QoS profiles. To enable the support of such profiles, an extended IMS architecture, relying on two adaptive resource management mechanisms, is proposed. Furthermore, simulations are used to evaluate the system performance. Compared to existing service differentiation solutions, our solution offers several benefits, such as: flexible QoS negotiation mechanisms, control over many communication aspects as means for differentiation, and a dynamic and adaptive resource management strategy.

Packet QoS Aware AMC Selection for 3G LTE of Evolved Packet System

3GPP evolved packet system (EPS) is an all-IP based system that supports various access networks such as LTE, HSPA/HSPA+ and non-3GPP networks. Recently, the support of IP flows with packet level QoS profiles has been added to the requirements of the EPS. This paper proposes an adaptive modulation and coding (AMC) scheme that supports the QoS of such IP flows in the 3G LTE access network of the EPS. Defining the retransmission as a critical factor for QoS, the proposed scheme applies different maximum packet error probability P max to each packet when selecting the AMC transmission mode. In determining P max , the QoS constraints as well as channel condition are considered, balancing two objectives: the satisfaction of the QoS and the maximization of spectral efficiency. Simulations show that it is able to reduce both delay violation and retransmission, while improving throughput in comparison with an existing scheme.

Adaptive Management of QoS Requirements for Wireless Multimedia Communications

We present a control model, which provides response time and bandwidth requirement adaptation in audio, video, and application sharing multipoint IP teleconferences for emerging wireless multimedia communications. The model is based on revealing feedback controls for multimedia call preparation and subsequent real time connection control. Case-based reasoning memory is used to associate real time congestion (connection) controls with call preparation controls and user QoS profiles. Web agents are used to capture user and application multimedia call profiles observed at the application layer and transfer them into the case memory. RTP statistics are used to identify the connection management feedback controls for the network layer. Real-time adaptation at the network layer and above is made possible by using hierarchical coding techniques. The proposed adaptive management architecture is illustrated by a case memory representation of call preparation feedback controls, RTP feedback control tests for providing audio stream bandwidth adaptation, and configuration of integrated experiments.

Performance evaluation of optimal aggregate-flow scheduling: a simulation study

Providing scalable QoS-sensitive services to applications with varying degrees of elasticity using aggregate-flow scheduling is a challenging problem. In a previous paper [Proc. IEEE/IFIP Int. Workshop Quality Service (2000) 211], we advanced a theoretical framework where an optimal differentiated services provisioning problem is formulated and solved to yield solutions for optimal per-hop control. In this paper, we extend our previous work by investigating performance evaluation and implementation issues associated with the induced optimal differentiated services architecture. We design a system that realizes the optimal per-hop control coupled with end-to-end adaptive QoS control, and implement a practical enhancement by introducing a scaling function which is applied to the TOS field label value in the IP header at each router. The scaling function allows the service provider to configure the per-hop control so as to export customized QoS separation—essential when shaping end-to-end absolute QoS over per-hop relative QoS-commensurate with the QoS profiles of the service provider's user base. We use simulation to study the structural and dynamical properties of differentiated services as affected by optimal aggregate-flow per-hop control.

IP QoS delivery in a broadband wireless local loop: MAC protocol definition and performance evaluation

The wireless approach to the last mile access (wireless local loop, known as WLL) is becoming increasingly attractive to network operators and service providers since it offers a flexible and cost-effective solution to enable delivery of even broadband services to end customers. In this paper, a full-blown broadband WLL network is presented. The proposal is based on the OFDM-CDMA technique, to which an added dynamic reservation/request MAC protocol is proposed, fully exploiting the OFDM-CDMA platform. Central to our proposal is the support of different QoS profiles, in the context of QoS aware networks. As a case study, the explicit presentation of the IETF integrated services support over our WLL system is addressed. An extensive performance evaluation focused on the MAC layer is then reported. We prove that our scheme achieves high utilization efficiency, as well as a fair share of the available radio capacity, even in the presence of highly heterogeneous traffic mix. Delay performance is provided for both reference traffic models, as well as for measured IP and MPEG traffic traces offered to the system.