A Virtual PEP for Web Optimization over a Satellite-Terrestrial Backhaul

The availability of network softwarization and virtualization technology in the field of telecommunications has opened the door to a radical review of the applications, protocols, and deployment models. In this evolving framework, old assumptions and constraints specific to satellite communications must be carefully re-assessed. To this aim, we revisit the role of the performance enhancing proxy (PEP), replaced by a chain of custom virtual network functions properly enabled to optimize common web traffic performance over a backhaul dynamically enabled with a supplementary satellite link. The resulting virtual PEP (vPEP) is compliant with the breakthrough virtualization and slicing paradigms and can fruitfully exploit the advanced features of the most recent IETF technologies such as QUIC and MPTCP

A REVIEW STUDY OF EUROPEAN R&D PROJECTS FOR SATELLITE COMMUNICATIONS IN 5G/6G ERA

Κατά τις τελευταίες δεκαετίες τα δορυφορικά συστήματα τηλεπικοινωνιών έχουν προσφέρει μια γκάμα από πολυμεσικές υπηρεσίες όπως δορυφορική τηλεόραση, δορυφορική τηλεφωνία και ευρυζωνική πρόσβαση στο διαδίκτυο. Οι μακροπρόθεσμες τεχνολογικές αναβαθμίσεις σε συνδυασμό με την προσθήκη νέων δορυφορικών συστημάτων γεωστατικής και ελλειπτικής τροχιάς και με την ενσωμάτωση τεχνολογιών πληροφορικής έχουν ωθήσει την αύξηση του μέγιστου εύρους των δορυφόρων στο 1Gbps σε μεμονωμένους δορυφόρους ενώ σε διάταξη αστερισμού μπορούν να ξεπεράσουν το 1 Tbps. Σε συνδυασμό με την μείωση του χρόνου απόκρισης σε ρυθμούς ανταγωνιστικούς με τις χερσαίες υποδομές ανοίγουν νέες ευκαιρίες και νέους ρόλους εντός ενός οικοσυστήματος ετερογενούς δικτύων 5ης γενιάς. Σε αυτήν την διατριβή, αξιολογούμε επιδοτούμενα επιστημονικά προγράμματα έρευνας και ανάπτυξης της Ευρωπαϊκής Επιτροπής Διαστήματος (ESA) και του προγράμματος επιδότησης Horizon 2020 της Ευρωπαϊκής Ένωσης, προκειμένου να εξηγήσουμε τις δυνατότητες των δορυφόρων εντός ενός ετερογενούς δικτύου 5ης γενιάς, αναφέρουμε συγκεκριμένα αυτά που αφορούν την εξέλιξη των δορυφορικών ψηφιακών συστημάτων και την ικανότητα ενσωμάτωσης τους σε τωρινές αλλά και μελλοντικές υποδομές χερσαίων τηλεπικοινωνιακών δικτύων μέσω της εμφάνισης νέων τεχνολογιών στις ηλεκτρονικές και οπτικές επικοινωνίες αέρος μαζί με την εμφάνιση τεχνολογιών πληροφορικής όπως της δικτύωσης βασισμένης στο λογισμικό και της εικονικοποίησης λειτουργιών δικτύου. Αναφερόμαστε στους στόχους του κάθε project ξεχωριστά και κατηγοριοποιημένα στους ακόλουθους τομείς έρευνας: -Συσσωμάτωση των δορυφόρων με τα επίγεια δίκτυα 5ης γενιάς με οργανωμένες μελέτες και στρατηγικές -Ενσωμάτωση των τεχνολογιών δικτύωσης βασισμένης στο λογισμικό και εικονικοποίησης λειτουργιών δικτύου στο δορυφορικών τμήμα των δικτύων 5ης γενιάς -Ο ρόλος των δορυφόρων σε εφαρμογές του διαδικτύου των πραγμάτων σε συνάφεια με τα χερσαία δίκτυα 5ης γενιάς -Ο ρόλος των δορυφόρων στην δίκτυα διανομής πολυμεσικού περιεχομένου & η επιρροή των πρωτοκόλλων διαδικτύου στην ποιότητα υπηρεσίας χρήστη κατά την διάρκεια μιας δορυφορικής σύνδεσης. -Μελλοντικές βελτιώσεις και εφαρμογές στα δορυφορικά συστήματα με έμφαση στα μελλοντικά πρότυπα του φυσικό επιπέδου Στο τέλος διαθέτουμε ένα παράρτημα που αφορά τεχνικές αναλύσεις στην εξέλιξη του φυσικού επιπέδου των δορυφορικών συστημάτων, συνοδευόμενο με την συσχετιζόμενη βιβλιογραφία για περαιτέρω μελέτη.Over the last decades satellite telecommunication systems offer many types of multimedia services like Satellite TV, telephony and broadband internet access. The long-term technological evolutions occurred into state-of-the-art satellite systems altogether with the addition of new high throughput geostatic and non-geostatic systems, individual satellites can now achieve a peak bandwidth of up to Gbps, and with possible extension into satellite constellation systems the total capacity can reach up to Tbps. Supplementary, with systems latency being comparable to terrestrial infrastructures and with integration of several computer science technologies, satellite systems can achieve new & more advanced roles inside a heterogeneous 5G network’s ecosystem. In this thesis, we have studied European Space Agency (ESA’s) and European Union’s (EU) Horizon 2020 Research and Development (R&D) funded projects in order to describe the satellite capabilities within a 5G heterogeneous network, mentioning the impact of the evolution of digital satellite communications and furthermore the integration with the state-of the art & future terrain telecommunication systems by new technologies occurred through the evolution of electronic & free space optical communications alongside with the integration of computer science’s technologies like Software Defined Networking (SDN) and Network Function Virtualization (NFV). In order to describe this evolution we have studied the concepts of each individual project, categorized chronically and individual by its scientific field of research. Our main scientific trends for this thesis are: -Satellite Integration studies & strategies into the 5G terrestrial networks -Integration of SDN and NFV technologies on 5G satellite component -Satellite’s role in the Internet of Things applications over 5G terrestrial networks -Satellite’s role in Content Distribution Networks & internet protocols impact over user’s Quality of Experience (QoE) over a satellite link -The future proposals upon the evolution of Satellite systems by upcoming improvements and corresponding standards Finally, we have created an Annex for technical details upon the evolution of physical layer of the satellite systems with the corresponding bibliography of this thesis for future study

Uma abordagem preditiva de DASH QoE baseada em aprendizado de máquina em multi-access edge computing

Orientador: Christian Rodolfo Esteve RothenbergDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de ComputaçãoResumo: O tráfego de serviços de vídeo multimídia está crescendo rapidamente nas redes móveis nos últimos anos. Os serviços de vídeo que usam técnicas de Dynamic Adaptive Streaming sobre HTTP (DASH) dominaram o tráfego total da Internet para transportar o tráfego de vídeo. Espera-se que as operadoras de rede móvel (Mobile Network Operators - MNOs) continuem atendendo a essa demanda crescente por tráfego de vídeo suportado por DASH, ao mesmo tempo em que fornecem uma alta qualidade de experiência (Quality of Experience - QoE) aos usuários finais. Além disso, as operadoras precisam ter um conhecimento claro acerca da qualidade de vídeo percebida pelos usuários finais e relacioná-la com o monitoramento em nível de rede, ou com informações de telemetria para identificação de problemas, análise da causa raiz e predição de padrões. Para garantir um gerenciamento de tráfego de rede com reconhecimento de QoE, um pré-requisito é que os MNOs monitorem o tráfego de rede passivamente e realizem medições efetivas de indicadores-chave de desempenho (Key Performance Indicators - KPIs) de QoE, como resoluções, eventos de paralisação, entre outros, que influenciam diretamente a percepção do usuário final. Muitas abordagens da literatura foram propostas para medir os KPIs com o objetivo de fornecer uma qualidade de serviço de vídeo aceitável. A maioria das soluções exige consciência de contexto do usuário final, o que não é viável do ponto de vista do MNO. No entanto, Deep Packet Inspection (DPI), outra solução mais amplamente usada para estimar os KPIs diretamente do tráfego de rede, não é mais uma solução conveniente para as operadoras devido à adoção de criptografia de streaming de vídeo fim-a-fim sobre TCP (HTTPs) e QUIC. Portanto, o aprendizado de máquina (Machine Learning - ML) passou a ser recentemente aceito como uma solução bem reconhecida para estimar KPIs de QoE, analisando os padrões de tráfego criptografados bem como estatísticas como qualidade de serviço (Quality of Service - QoS). Este trabalho apresenta uma abordagem mais refinada e leve, baseada em aprendizado de máquina, denominada Edge QoE Probe, para estimar QoE do usuário final para o serviço de vídeo DASH, monitorando passivamente o tráfego de rede criptografado na borda da rede. Nossa abordagem pode avaliar vários KPIs de QoE, como por exemplo resolução, taxa de bits, proporção de paralisação, entre outros, tanto em tempo real quanto por sessão. Além disso, neste trabalho investigamos o desempenho do vídeo DASH sobre o protocolo de transporte tradicional TCP (HTTPs) e QUIC. Para este propósito, avaliamos experimentalmente diferentes traces de rede celular em um ambiente emulado de alta fidelidade e comparamos o desempenho comportamental de algoritmos Adaptive Bitrate Streaming (ABS) considerando KPIs de QoE sobre TCP (HTTPs) e QUIC. Nossos resultados empíricos mostram que os algoritmos tradicionais de ABS usando QUIC como transporte precisariam alterações específicas para melhorar o desempenho em termos de QoE de vídeo baseados em DASHAbstract: Multimedia video services traffic is rapidly growing in mobile networks in recent years. Video services using Dynamic Adaptive Streaming over HTTP (DASH) techniques have dominated the total internet traffic to carry video traffic. Mobile Network Operators (MNOs) are expected to run on with this growing demand for DASH-supported video traffic while providing a high Quality of Experience (QoE) to the end-users. Besides, operators need to have a crystal notion of video quality perceived by the end-users and correlate them with network-level monitoring or telemetry information for problem identification, root cause analysis, and pattern prediction. To ensure QoE–aware network traffic management, a prerequisite for the MNOs is to monitor the network traffic passively and measure objective QoE Key Performance Indicators (KPIs) (such as resolutions and stalling events) effectively that directly influence end-user subjective feedback. Many literature approaches have been proposed to measure the KPIs aimed to deliver acceptable video service quality. Most of the solutions require end-user awareness, which is not viable from the MNOs' perspective. However, Deep Packet Inspection (DPI), another most widely used solution to estimate the KPIs directly from network traffic, is not a convenient solution anymore for the operators due to the adoption of end-to-end video streaming encryption over TCP (HTTPs) and QUIC transport protocol. Hence, in recent, Machine Learning (ML) has been accepted as a well-recognized solution for estimating QoE KPIs by analyzing the encrypted traffic patterns and statistics as Quality of Service (QoS). This work presents an ML-based lightweight and fine-grained Edge QoE Probe approach to estimate the end-user QoE for DASH video service by passively monitoring the encrypted network traffic on the edge of the network. Our approach can assess numerous QoE KPIs (such as resolution, bit-rate, quality switches, startup delay, and stall ratio) both in a real-time and per-session manner. Moreover, we investigate the DASH video service performance over the traditional TCP (HTTPs) and QUIC transport protocol in this work. For this purpose, we experimentally evaluate different cellular network traces in a high-fidelity emulated testbed and compare the behavioral performance of Adaptive Bitrate Streaming (ABS) algorithms considering QoE KPIs over TCP (HTTPs) and QUIC. Our empirical results show that QUIC suffers from traditional state-of-the-art ABS algorithms' ineffectiveness to improve video streaming performance without specific changesMestradoEngenharia de ComputaçãoMestre em Engenharia ElétricaFuncam

RAPID: a RAN-aware Performance Enhancing Proxy for High Throughput Low Delay Flows in MEC Networks

International audience5G enhanced Mobile broadband (eMBB) aims to provide users with a peak data rate of 20 Gbps in the Radio Access Network (RAN). However, since most Congestion Control Algorithms (CCAs) rely on startup and probe phases to discover the bottleneck bandwidth, they cannot quickly utilize the available RAN bandwidth and adapt to fast capacity changes without introducing large delay increase, especially when multiple flows are sharing the same Radio Link Control (RLC) buffer. To tackle this issue, we propose RAPID, a RAN-aware proxy-based flow control mechanism that prevents CCAs from overshooting more than the available RAN capacity while allowing near optimal link utilization. Based on analysis of up-to-date radio information using Multi-access Edge Computing (MEC) services and packet arrival rates, RAPID is able to differentiate slow interactive flows from fast download flows and allocate the available bandwidth accordingly. Our simulation and experimentation results with concurrent Cubic and BBR flows show that RAPID can reduce delay increase by a factor of 10 to 50 in both Line-of-Sight (LOS) and Non-LOS (NLOS) conditions while preserving high throughput in both 4G and 5G environments

Enhancing QUIC over Satellite Networks

The use of Satellite Communication (SATCOM) networks for broadband connectivity has recently seen an increase in popularity due to, among other factors, the rise of the latest generations of cellular networks (5G/6G) and the deployment of high-throughput satellites. In parallel, major advances have been witnessed in the context of the transport layer: first, the standardization and early deployment of QUIC, a new-generation and general-purpose transport protocol; and second, modern congestion control proposals such as the Bottleneck Bandwidth and Round-trip propagation time (BBR) algorithm. Even though satellite links introduce several challenges for transport layer mechanisms, mainly due to their long propagation delay, satellite Internet providers have relied on TCP connection-splitting solutions implemented by Performance-Enhancing Proxies (PEPs) to greatly overcome many of these challenges. However, due to QUIC's fully encrypted nature, these performance-boosting solutions become nearly impossible for QUIC traffic, leaving it in great disadvantage when competing against TCP-PEP. In this context, IETF QUIC WG contributors are currently investigating this matter and suggesting new solutions that can help improve QUIC's performance over SATCOM. This thesis aims to study some of these proposals and evaluate them through experimentation using a real network testbed and an emulated satellite link

A Novel Approach to Transport-Layer Security for Spacecraft Constellations

Spacecraft constellations seek to provide transformational services from increased environmental awareness to reduced-latency international finance. This connected future requires trusted communications. Transport-layer security models presume link characteristics and encapsulation techniques that may not be sustainable in a networked constellation. Emerging transport layer protocols for space communications enable new transport security protocols that may provide a pragmatic alternative to deploying Internet security mechanisms in space. The Bundle Protocol (BP) and Bundle Protocol Security (BPSec) protocol have been designed to provide such an alternative. BP is a store-and-forward alternative to IP that carries session information as secondary headers. BPSec uses BP’s featureful secondary header mechanism to hold security information and security results. In doing so, BPSec provides an in-packet augmentation alternative to security by encapsulation. BPSec enables features such as security-at-rest, separate encryption/signing of individual protocol headers, and the ability to add secondary headers and secure them at waypoints in the network. These features provided by BPSec change the system trades associated with networked constellations. They enable security at rest, secure content caching, and deeper inspection at gateways otherwise obscured by tunneling

Network-aware video streaming for future media Internet

272 p

Reducing Internet Latency : A Survey of Techniques and their Merit

Bob Briscoe, Anna Brunstrom, Andreas Petlund, David Hayes, David Ros, Ing-Jyh Tsang, Stein Gjessing, Gorry Fairhurst, Carsten Griwodz, Michael WelzlPeer reviewedPreprin