Duplicating RTP streams

Packet loss is undesirable for real-time multimedia sessions but can occur due to a variety of reasons including unplanned network outages. In unicast transmissions, recovering from such an outage can be difficult depending on the outage duration, due to the potentially large number of missing packets. In multicast transmissions, recovery is even more challenging as many receivers could be impacted by the outage. For this challenge, one solution that does not incur unbounded delay is to duplicate the packets and send them in separate redundant streams, provided that the underlying network satisfies certain requirements. This document explains how Real-time Transport Protocol (RTP) streams can be duplicated without breaking RTP or RTP Control Protocol (RTCP) rule

Congestion Control using FEC for Conversational Multimedia Communication

In this paper, we propose a new rate control algorithm for conversational multimedia flows. In our approach, along with Real-time Transport Protocol (RTP) media packets, we propose sending redundant packets to probe for available bandwidth. These redundant packets are Forward Error Correction (FEC) encoded RTP packets. A straightforward interpretation is that if no losses occur, the sender can increase the sending rate to include the FEC bit rate, and in the case of losses due to congestion the redundant packets help in recovering the lost packets. We also show that by varying the FEC bit rate, the sender is able to conservatively or aggressively probe for available bandwidth. We evaluate our FEC-based Rate Adaptation (FBRA) algorithm in a network simulator and in the real-world and compare it to other congestion control algorithms

Scalable Guaranteed-Bandwidth Multicast Service in Software Defined ISP networks

International audienceNew applications where anyone can broadcast video are becoming very popular on smartphones. With the advent of high definition video, ISP providers may take the opportunity to propose new high quality broadcast services to their clients. Because of its centralized control plane, Software Defined Networking (SDN) seems an ideal way to deploy such a service in a flexible and bandwidth-efficient way. But deploying large scale multicast services on SDN requires smart group membership management and a bandwidth reservation mechanism to support QoS guarantees that should neither waste bandwidth nor impact too severely best effort traffic. In this paper, we propose a Network Function Virtualization based solution for Software Defined ISP networks to implement scalable multicast group management. Then, we propose the Lazy Load balancing Multicast (L2BM) routing algorithm for sharing the network capacity in a friendly way between guaranteed-bandwidth multicast traffic and best-effort traffic. Our implementation of the framework made on Floodlight controllers and Open vSwitches is used to study the performance of L2BM

“Diseño y simulación de una red de transporte de video en tiempo real en IPV4 mediante protocolo Unicast, dirigido a empresas de post-producción/edición de contenido multimedia con calidad de servicio”

Este trabajo presenta el diseño y simulación de una de red transporte de aplicaciones multimedia, entre las fuentes de generación de contenido y las empresas de post producción. La red de datos que interconecta estos dos sitios es conocida como red de CONTRIBUCIÓN. Estas redes de comunicaciones deben transportar un contenido inédito, que no tiene copias, que ha sido obtenido en las calles, en estudios de producción o en eventos deportivos, con alta disponibilidad, fiabilidad y bajo retardo. Las redes contribución tienen la característica de ser muy estables, y cuyo crecimiento es muy lento y controlado a diferencia de, por ejemplo, las redes secundarias de distribución de IPTV, que son muy dinámicas