Path signalling in a wireless back-haul network integrating unidirectional broadcast technologies

The black-haul infrastructures of today's wireless operators must support the triple-play services demanded by the market or regulatory bodies. To cope with increasing capacity demand, in our previous work, we have developed a cost-effective heterogeneous layer 2.5 wireless back-haul (WiBACK) architecture, which leverages the native multicast capabilities of broadcast technologies such as DVB to off-load high-bandwidth broadcast content delivery. Furthermore, our architecture provides support for unidirectional technologies on the data and the control plane. This adopts a centralized coordinator approach, in which coordinator nodes install so-called management and data pipes. No routing state is kept at plain WiBACK nodes, which merely store QoS-aware pipe forwarding state. Consequently, the architecture requires a reliable protocol to push resource allocation and pipe forwarding state into the network, considering possibly unidirectional connectivity. Such a protocol, whose task is related to MPLS label distribution, is essential during the initial forming of WiBACK topologies and during regular network operations to reliably manage the data pipes. In this paper, we present a novel approach to extend our IEEE 802.21-inspired WiBACK TransportService and, based upon this, the design of an RSVP-TE-style pipe signalling protocol using nested hop-by-hop request/response MIH transactions that supports signalling over unidirectional technologies. A thorough evaluation and successful testbed deployments show that this protocol reliably signals pipe state even under high loss conditions

The MobyDick Project: A Mobile Heterogeneous All-IP Architecture

Proceedings of Advanced Technologies, Applications and Market Strategies for 3G (ATAMS 2001). Cracow, Poland: 17-20 June, 2001.This paper presents the current stage of an IP-based architecture for heterogeneous environments, covering UMTS-like W-CDMA wireless access technology, wireless and wired LANs, that is being developed under the aegis of the IST Moby Dick project. This architecture treats all transmission capabilities as basic physical and data-link layers, and attempts to replace all higher-level tasks by IP-based strategies. The proposed architecture incorporates aspects of mobile-IPv6, fast handover, AAA-control, and Quality of Service. The architecture allows for an optimised control on the radio link layer resources. The Moby dick architecture is currently under refinement for implementation on field trials. The services planned for trials are data transfer and voice-over-IP.Publicad

QoS Provisioning in Converged Satellite and Terrestrial Networks: A Survey of the State-of-the-Art

It has been widely acknowledged that future networks will need to provide significantly more capacity than current ones in order to deal with the increasing traffic demands of the users. Particularly in regions where optical fibers are unlikely to be deployed due to economical constraints, this is a major challenge. One option to address this issue is to complement existing narrow-band terrestrial networks with additional satellite connections. Satellites cover huge areas, and recent developments have considerably increased the available capacity while decreasing the cost. However, geostationary satellite links have significantly different link characteristics than most terrestrial links, mainly due to the higher signal propagation time, which often renders them not suitable for delay intolerant traffic. This paper surveys the current state-of-the-art of satellite and terrestrial network convergence. We mainly focus on scenarios in which satellite networks complement existing terrestrial infrastructures, i.e., parallel satellite and terrestrial links exist, in order to provide high bandwidth connections while ideally achieving a similar end user quality-of-experience as in high bandwidth terrestrial networks. Thus, we identify the technical challenges associated with the convergence of satellite and terrestrial networks and analyze the related work. Based on this, we identify four key functional building blocks, which are essential to distribute traffic optimally between the terrestrial and the satellite networks. These are the traffic requirement identification function, the link characteristics identification function, as well as the traffic engineering function and the execution function. Afterwards, we survey current network architectures with respect to these key functional building blocks and perform a gap analysis, which shows that all analyzed network architectures require adaptations to effectively support converged satellite and terrestrial networks. Hence, we conclude by formulating several open research questions with respect to satellite and terrestrial network convergence.This work was supported by the BATS Research Project through the European Union Seventh Framework Programme under Contract 317533

Survey of Transportation of Adaptive Multimedia Streaming service in Internet

[DE] World Wide Web is the greatest boon towards the technological advancement of modern era. Using the benefits of Internet globally, anywhere and anytime, users can avail the benefits of accessing live and on demand video services. The streaming media systems such as YouTube, Netflix, and Apple Music are reining the multimedia world with frequent popularity among users. A key concern of quality perceived for video streaming applications over Internet is the Quality of Experience (QoE) that users go through. Due to changing network conditions, bit rate and initial delay and the multimedia file freezes or provide poor video quality to the end users, researchers across industry and academia are explored HTTP Adaptive Streaming (HAS), which split the video content into multiple segments and offer the clients at varying qualities. The video player at the client side plays a vital role in buffer management and choosing the appropriate bit rate for each such segment of video to be transmitted. A higher bit rate transmitted video pauses in between whereas, a lower bit rate video lacks in quality, requiring a tradeoff between them. The need of the hour was to adaptively varying the bit rate and video quality to match the transmission media conditions. Further, The main aim of this paper is to give an overview on the state of the art HAS techniques across multimedia and networking domains. A detailed survey was conducted to analyze challenges and solutions in adaptive streaming algorithms, QoE, network protocols, buffering and etc. It also focuses on various challenges on QoE influence factors in a fluctuating network condition, which are often ignored in present HAS methodologies. Furthermore, this survey will enable network and multimedia researchers a fair amount of understanding about the latest happenings of adaptive streaming and the necessary improvements that can be incorporated in future developments.Abdullah, MTA.; Lloret, J.; Canovas Solbes, A.; García-García, L. (2017). Survey of Transportation of Adaptive Multimedia Streaming service in Internet. Network Protocols and Algorithms. 9(1-2):85-125. doi:10.5296/npa.v9i1-2.12412S8512591-

QoS Abstraction Layer in 4G Access Networks

Tese de Mestrado. Redes e Serviços de Comunicação. Faculdade de Engenharia. Universidade do Porto. 200