Quality of Service in Quantum Networks

In the coming years, quantum networks will allow quantum applications to thrive thanks to the new opportunities offered by end-to-end entanglement of qubits on remote hosts via quantum repeaters. On a geographical scale, this will lead to the dawn of the Quantum Internet. While a full-blown deployment is yet to come, the research community is already working on a variety of individual enabling technologies and solutions. In this paper, with the guidance of extensive simulations, we take a broader view and investigate the problems of Quality of Service (QoS) and provisioning in the context of quantum networks, which are very different from their counterparts in classical data networks due to some of their fundamental properties. Our work leads the way towards a new class of studies that will allow the research community to better understand the challenges of quantum networks and their potential commercial exploitation.Comment: Submitted to the IEEE for possible publicatio

In-Network Computing With Function as a Service at the Edge

Offloading computation from user devices to nodes with processing capabilities at the edge of the network is a major trend in today's network/service architectures. At the same time, serverless computing has gained a huge traction among the cloud computing technologies and has, thus, promoted the adoption of Function-as-a-Service (FaaS). The latter has some characteristics that make it generally suitable to edge applications, except for its cumbersome support of stateful applications. This work is set to provide a broad view on the options available for supporting stateful FaaS, which are distilled into four reference execution models that differ on where the state resides. While further investigation is needed to advance our understanding of the opportunities offered by in-network computing through stateful FaaS, initial insights are provided by means of a qualitative analysis of the four alternatives and their quantitative comparison in a simulator

Routing in Quantum Repeater Networks with Mixed Noise Figures

Quantum network holds the key to the next generation of secure communication, long-distance communication, and quantum internet. Due to inherent quantum effects, routing in the quantum network is a major challenge. This study explores a realistic approach to routing in quantum networks which aims to mirror real-world networks by segregating sources and destinations from the network. By addressing practical constraints we examine the impact of heterogeneous nodes on network performance. In particular, we focused on performance in terms of the ratio of high-quality to total nodes and path establishment order. This work unveils relationships between them and communication path fidelity. It highlights the critical role of the fraction of high-quality nodes in end-to-end fidelity and explores the trade-offs between upgrading all nodes to high quality or retaining a subset of lower-quality nodes. Our simulations show that incorporating the knowledge of node quality not only helps in strategically boosting the fidelities of some of the routing paths but also reduces the number of blocked paths in the quantum network.Comment: 6 pages, 6 figures, IEEE ICC 2024 conferenc

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t is common knowledge that over the last decade there has been a major boost in communication networks. In fact, the development of high-performance backbone networks was immediately followed by the rapid dissemination of broadband wired access technologies, such as leased lines based on fiber-optic links, cable modems using coaxial systems, and digital subscriber line (xDSL) access networks. This gave users a whole new class of services that exploit the increasing number of available network resources. Many new services are based on multimedia applications, such as voice over IP (VoIP), video conferencing, video on demand (VoD), massive online gaming, and peer-to-peer. Unlike traditional TCP/IP services, multimedia applications usually require strict network guarantees such as reserved bandwidth or bounded delays. The broadband access phenomenon has been investigated by the International Telecommunication Union (ITU), which reported in [1] that Broadband Wireless Access (BWA), although still in the early stage of its growth, is one of the most promising solutions for broadband access. Standards for BWA are being developed within IEEE Project 802, working group 16, also referred to as 802.16 The challenge for BWA networks is in providing quality of service (QoS) simultaneously to services with very different characteristics. QoS support in wireless networks is a much more difficult task than in wired networks, mainly because the characteristics of a wireless link are highly variable and unpredictable, both on a time-dependent basis and a locationdependent basis. To cope with such issues, QoS in wireless networks is usually managed at the medium access control (MAC) layer. Despite the fact that the launch of 802.16 products has already been announced on the market by several manufacturers, the research literature still lacks a sufficient number of studies that specifically address the analysis of the 802.16 MAC protocol. In [4] the author performed a hybrid analytical-simulative analysis of the effect on the system performance of several MAC mechanisms, including the fragmentation of service data units (SDUs) and the padding of OFDM symbols. The performance with the time-division duplex (TDD) mode was partially analyzed in In this article, we review and analyze the mechanisms for supporting QoS at the IEEE 802.16 MAC layer. We then analyze by simulation the performance of IEEE 802.16 in two application scenarios, which consist of providing last-mile Internet access for residential and SME subscribers, respectively. Our analysis is aimed at showing the effectiveness of the 802.16 MAC protocol in providing differentiated services to applications with different QoS requirements, such as VoIP and Web. Abstract During the last few years, users all over the world have become more and more accustomed to the availability of broadband access. This has boosted the use of a wide variety both of established and recent multimedia applications. However, there are cases where it is too expensive for network providers to serve a community of users. This is typically the case in rural and suburban areas, where there is slow deployment (or no deployment at all) of traditional wired technologies for broadband access (e.g., cable modems, xDSL). In those cases, the most promising opportunity rests with Broadband Wireless Access technologies, such as the IEEE 802.16, also known as WiMAX. One of the features of the MAC layer of 802.16 is that it is designed to differentiate service among traffic categories with different multimedia requirements. This article focuses on mechanisms that are available in an 802.16 system to support quality of service (QoS) and whose effectiveness is evaluated through simulation. Quality of Servic

End-to-End Bandwidth Reservation in IEEE 802.16 Mesh Networks

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Serverless Vehicular Edge Computing for the Internet of Vehicles

Rapid growth in the popularity of smart vehicles and increasing demand for vehicle autonomy brings new opportunities for vehicular edge computing (VEC). VEC aims at offloading the time-sensitive computational load of connected vehicles to edge devices, e.g., roadside units. However, VEC offloading raises complex resource management challenges and, thus, remains largely inaccessible to automotive companies. Recently, serverless computing emerged as a convenient approach to the execution of functions without the hassle of infrastructure management. In this work, we propose the idea of serverless VEC as the execution paradigm for Internet of Vehicles applications. Further, we analyze its benefits and drawbacks as well as identify technology gaps. We also propose emulation as a design, evaluation, and experimentation methodology for serverless VEC solutions. Using our emulation toolkit, we validate the feasibility of serverless VEC for real-world traffic scenarios.We would like to thank Asama Qureshi for his contribution to the traffic visualizer application. We would also like to acknowledge support through the Australian Research Council's funded projects DP230100081 and FT180100140. This work is also partially supported by the Spanish Ministry of Economic Affairs and Digital Transformation, the European Union-NextGenerationEU through the UNICO 5G IþD SORUS project and by the NWO OffSense, EU Horizon Graph-Massivizer and CLOUDSTARS projects

Performance Evaluation of the IEEE 802.16 MAC Protocol for Broadband Wireless Access

The IEEE 802.16 is establishing itself as one of the leader technologies in the context of Broadband Wireless Access (BWA), as corroborated by the huge number companies that have joined the WiMAX Forum since it was formed in June of 2001 to promote the adoption of IEEE 802.16 compliant equipment by operators of BWA systems. Since its first release in 2001, the IEEE 802.16 standard included native support for Quality of Service (QoS) at the Medium Access Control (MAC) layer, with several mechanisms to support different types of applications, classifi ed by the standard into four scheduling services. However, the standard does not specify the algorithms to actually provide QoS support by means of these mechanisms. This allows any manufacturer to implement its own optimized proprietary algorithms, thus gaining a competitive advantage over rivals. The IEEE 802.16 standard provides four diff erent scheduling services: Unsolicited Grant Service (UGS), real-time Polling Service (rtPS), non-real-time Polling Service (nrtPS), and Best Effort (BE). This work is aimed at verifying, via simulation, the effectiveness of rtPS, nrtPS and BE in managing traffic generated by data and multimedia sources. Performance is assessed for an IEEE 802.16 wireless system working in Point-to-Multipoint (PMP) mode, with Frequency Division Duplex (FDD), and with full-duplex Subscriber Stations (SSs). Our results show that the performance of the system, in terms of (e.g.) throughput and delay, depends on several factors: the frame duration, the mechanisms for requesting bandwidth (uplink only), the multimedia traffic type, and the offered load partitioning, i.e. the way traffic is distributed among SSs, connections within each SS and traffic sources within each connection. Finally, we propose an algorithm, namely Half-Duplex Allocation algorithm (HDA), that can be employed by the BS to serve SSs with half-duplex capabilities (HD-SSs) in Frequency Division Duplexing (FDD) mode. Based on the extensive simulations, we show that the performance degradation of HD-SSs, with respect to SSs with full-duplex capabilities (FD-SSs), is negligible, provided that HDA is employed by the BS