Seamless multimedia delivery within a heterogeneous wireless networks environment: are we there yet?

The increasing popularity of live video streaming from mobile devices such as Facebook Live, Instagram Stories, Snapchat, etc. pressurises the network operators to increase the capacity of their networks. However, a simple increase in system capacity will not be enough without considering the provisioning of Quality of Experience (QoE) as the basis for network control, customer loyalty and retention rate and thus increase in network operators revenue. As QoE is gaining strong momentum especially with increasing users’ quality expectations, the focus is now on proposing innovative solutions to enable QoE when delivering video content over heterogeneous wireless networks. In this context, this paper presents an overview of multimedia delivery solutions, identifies the problems and provides a comprehensive classification of related state-of-the-art approaches following three key directions: adaptation, energy efficiency and multipath content delivery. Discussions, challenges and open issues on the seamless multimedia provisioning faced by the current and next generation of wireless networks are also provided

A Performance Analysis Model of TCP over Multiple Heterogeneous Paths for 5G Mobile Services

Driven by the primary requirement of emerging 5G mobile services, the demand for concurrent multipath transfer (CMT) is still prominent. Yet, multipath transport protocols are not widely adopted and TCP-based CMT schemes will still be in dominant position in 5G. However, the performance of TCP flow transferred over multiple heterogeneous paths is prone to the link quality asymmetry, the extent of which was revealed to be significant by our field investigation. In this paper, we present a performance analysis model for TCP over multiple heterogeneous paths in 5G scenarios, where both bandwidth and delay asymmetry are taken into consideration. The evaluation adopting parameters from field investigation shows that the proposed model can achieve high accuracy in practical environments. Some interesting inferences can be drawn from the proposed model, such as the dominant factor that affect the performance of TCP over heterogeneous networks, and the criteria of determining the appropriate number of links to be used under different circumstances of path heterogeneity. Thus, the proposed model can provide a guidance to the design of TCP-based CMT solutions for 5G mobile services

Avaliação de estabilidade de transmissões de vídeo por protocolo de transporte multicaminho

Orientador : Prof. Dr. Eduardo Parente RibeiroCoorientador : Prof. Dr. Carlos Marcelo PedrosoDissertação (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia Elétrica. Defesa: Curitiba, 23/02/2017Inclui referências : p. 70-75Resumo: A evoluc¸a˜ o tecnolo' gica de dispositivos mo' veis e o aumento da disponibilidade de redes IP, criam novas oportunidades para distribuic¸a˜ o de conteu' do multimedia pela Internet. Atualmente os usua' rios teˆ m a possibilidade de acessar filmes, pec¸as de teatros, concertos de mu' sica transmitidos ao vivo ou armazenados sob-demanda. Aplicac¸o˜ es de tempo-real requerem alta qualidade de servic¸o, na˜ o sendo tolerantes a variac¸o˜ es do atraso me' dio por exemplo. Neste contexto, o delay-centric foi proposto para realizar handover entre redes mo' veis no protocolo SCTP. Sua proposta de realizar a troca de caminho utilizando o valor do atraso me' dio suavi- zado mostrou uma melhora significativa quando utilizado em aplicac¸o˜ es de tempo-real. Va' rios autores tem estudado a utilizac¸a˜ o do SCTP padra˜ o, do CMT e do CMT-PF em transmisso˜ es de v'?deo de tempo real. Este trabalho se propoˆ s a estudar a estabilidade de transmisso˜ es de v'?deo HD com diferentes caracter'?sticas de GOP, por protocolos de transporte multicaminho. Simulac¸o˜ es foram realizadas com trac¸ados de v'?deo de caracter'?sticas distintas e foram anali- sados, para fins de comparac¸a˜ o, o comportamento do delay-centric com diferentes histereses, SCTP padra˜ o, CMT e do CMT-PF. Foram utilizados cena' rios com va' rios n'?veis de diversidade e observadas me' tricas de atraso me' dio, Goodput, justic¸a na divisa˜ o do throughput e trhoughput me' dio nas interfaces dos agentes que enviavam e recebiam o v'?deo. Nos cena' rios com dois e treˆ s caminhos completamente disjuntos, os resultados obtidos confirmaram os dados conti- dos na literatura onde o delay-centric, independente da histerese, teve desempenho igual ou superior do CMT e ao CMT-PF. O SCTP Padra˜ o na˜ o se beneficiou da existeˆ ncia de mu' ltiplos caminhos, obtendo o pior desempenho dentre todos os protocolos estudados nos cena' rios com dois e treˆ s caminhos completamente disjuntos. Entretanto, no cena' rio com treˆ s no' s de acesso interligados a dois cores, com duas redes de acesso compartilhando um core, os resul- tados indicaram que o delay-centric sem histerese obteve o melhor desempenho dentre todos os protocolos estudados e o SCTP Padra˜ o mostrou melhor desempenho que o CMT, CMT-PF e delay-centric com histerese de 10ms, 20ms e 30ms. Palavras-chave: SCTP. Delay-centric. Multihoming.Abstract: The mobile devices technological evolution and the increased availability of IP networks, create new opportunities for multimedia content distribution over Internet. Nowadays, users have ac- cess to movies, plays or music concerts live over demand via video streaming over the Internet. Real-time applications require high quality service and are not tolerant to delay variations. The delay-centric was initially proposed to make the handover between mobile networks in SCTP by using the smoothed round trip time and delivering a higher user experience on real-time appli- cations. Other authors have studied the use of CMT and CMT-PF in real-time video streaming. The main objective of this work is to study the stability of HD video streaming, with different GOP characteristics, using multipath transport protocols. Video traces were used in the simu- lations with various path configurations to compare the behavior of delay-centric with different hysteresis, standard SCTP, CMT and CMT-PF. Results were analyzed using the metrics of de- lay, jitter, Goodput, mean throughput and throughput division justice. In scenarios with two or tree disjoint paths, the results confirmed the previous results on the literature that the delay- centric, independent of hysteresis level, have same or better performance when compared to CMT and CMT-PF. The standard SCTP do not take advantage of the multiple disjoint paths, having the worst performance when compared to the other protocols. In scenarios with tree access nodes connected to two cores, with two access networks sharing the same core, the results showed that the delay-centric with no hysteresis 5have the best performance in compa- rison to the other protocols, followed by the standard SCTP that presented better performance than CMT, CMT-PF and delay-centric with 10ms, 20ms, 30ms of hysteresis respectively. Key words: SCTP. Delay-centric. Multihoming