Encaminhamento Anycast em redes IPv6

Dissertação de mestrado integrado em Engenharia de ComunicaçõesO aparecimento do protocolo de comunicação Internet Protocol version 6 (IPv6) introduziu um novo paradigma de comunicação, denominado anycast (um-para-um-de-muitos). Este novo paradigma, utiliza o conceito de grupo, à semelhança do que acontece com o multicast, mas em oposição a este, a informação é enviada apenas para um dos membros do grupo (tipicamente o mais próximo) e não para todos. Embora já se tenham passado alguns anos desde o seu aparecimento, o anycast tem sofrido uma lenta evolução, contribuindo para esta situação o facto de não existir ainda um protocolo normalizado, que permita às aplicações usar de forma generalizada este paradigma de comunicação. Tradicionalmente as soluções para o problema de encaminhamento anycast são simplesmente baseadas no encaminhamento unicast sem alterações. No entanto, e tratando-se de um paradigma que usa o conceito de grupo, é de esperar que os protocolos de encaminhamento multicast, ou alguma variante destes, possam vir a constituir uma boa solução para a implementação do anycast ao nível da rede. A presente dissertação apresenta um levantamento de propostas relacionadas com o tema e propõe um novo protocolo de encaminhamento anycast baseado no protocolo Protocol Independent Multicast - Sparse Mode (PIM-SM), denominado Tree-based Anycast Protocol (TAP). As alterações propostas ao protocolo PIM-SM são apresentadas na especificação do sistema, tendo sido o seu correto funcionamento aferido recorrendo ao Network Simulator 2 (ns-2.35).The introduction of the new Internet Protocol version 6 (IPv6), came with a new communication paradigm, named anycast. This new paradigm, uses the group as a concept, similar to what happens with multicast, but in opposition to this, the information is sent only for one of the members on the group (usually the closest one) and not for all. Although some years have passed since its appearance, anycast had a slow development, being the main reason the fact that it doesn't have a standard protocol that allows applications to use widely this communication paradigm. The solutions for the anycast routing problem, traditionally, are based on unicast routing without any changes. However, and being this a paradigm that uses the group concept, it's expected that multicast routing protocols, or some kind of variant, would be a good solution to implement an anycast network-based protocol. This dissertation presents a survey of proposed anycast protocols and suggests a new routing protocol based on Protocol Independent Multicast - Sparse Mode (PIM-SM), designated as Tree-based Anycast Protocol (TAP). The chapter of the system specification introduce the changes to the protocol PIM-SM, and the correct behaviour measured using the Network Simulator 2 (ns-2.35)

Multicast using PIM-SM in Broadband Satellite Multimedia Systems

The approach currently being taken by ETSI (BSM) to standardisation for Multicast PIM-SM protocols is described. This paper describes methods, architectures and adaptations to support IP-multicast services efficiently across IP-based broadband multimedia satellite systems. This work has recently begun and the final objective is to arrive at a consensus for a standard on this subject

Multicast Mobility in Mobile IP Version 6 (MIPv6) : Problem Statement and Brief Survey

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Performance Analysis of Protocol Independent Multicasting-Dense Mode in Low Earth Orbit Satellite Networks

This research explored the implementation of Protocol Independent Multicasting - Dense Mode (PIM-DM) in a LEO satellite constellation. PIM-DM is a terrestrial protocol for distributing traffic efficiently between subscriber nodes by combining data streams into a tree-based structure, spreading from the root of the tree to the branches. Using this structure, a minimum number of connections are required to transfer data, decreasing the load on intermediate satellite routers. The PIM-DM protocol was developed for terrestrial systems and this research implemented an adaptation of this protocol in a satellite system. This research examined the PIM-DM performance characteristics which were compared to earlier work for On- Demand Multicast Routing Protocol (ODMRP) and Distance Vector Multicasting Routing Protocol (DVMRP) - all in a LEO satellite network environment. Experimental results show that PIM-DM is extremely scalable and has equivalent performance across diverse workloads. Three performance metrics are used to determine protocol performance in the dynamic LEO satellite environment, including Data-to- Overhead ratio, Received-to-Sent ratio, and End-to-End Delay. The OPNET® simulations show that the PIM-DM Data-to-Overhead ratio is approximately 80% and the protocol reliability is extremely high, achieving a Receive-to-Sent ratio of 99.98% across all loading levels. Finally, the PIM-DM protocol introduces minimal delay, exhibiting an average End-to-End Delay of approximately 76 ms; this is well within the time necessary to support real-time communications. Though fundamental differences between the DVMRP, ODMRP, and PIM-DM implementations precluded a direct comparison for each experiment, by comparing average values, PIM-DM generally provides equivalent or better performance

Performance evaluation of multicast routing on IPv4 and IPv6 networks

Even though the transition from IPv4 to IPv6 has not been realized at the pace that it was anticipated, eventually with the depletion of IPv4 address space and the ever-growing demands of the Internet, the transition is inevitable. In the rapidly evolving world of technology, multimedia applications and voice/video conferencing are fast finding their ways into the Internet and corporate networks. Multicast routing protocols run over unicast routing protocols to provide efficient routing of such applications. This thesis was aimed at understanding how the transition from IPv4 to IPv6 would impact multicast routing. The multicast routing protocol Protocol Independent Multicast-Sparse Mode (PIM-SM) was used over both IPv4 and IPv6 networks and a mixed IPv4-IPv6 network. Parameters such as protocol overheads, throughput and jitter were evaluated in a lab environment using jperf

Multicast Delivery of IPTV Over the Internet

Television represents one of the greatadvancements in information delivery. Traditionally, televisionservice has been delivered using dedicated communicationmethods such as terrestrial and satellite based wirelesstransmissions and fixed cable based transmissions. Some of thesedelivery mechanisms have advanced and now provide servicesincluding voice and Internet access. Another communicationmethod, traditional telephone service, has greatly improvedand expanded to deliver services such as television and Internetaccess.This convergence of service provides cost savings, allowingproviders to utilize existing communication networks to deliveradditional services to its customers, often at minimal or zeroinfrastructure cost. One disadvantage of this method is customerreach is still limited to those with access to dedicated serviceprovider networks. The ability to disengage television servicefrom these dedicated networks and move it to a more ubiquitousnetwork would greatly improve the customer reach of theproviders.The most obvious network choice for a delivery mediumis the Internet. Given that television delivery mechanisms havealready started the progression towards IPTV, the service isa natural fit. One issue hindering this transition is bandwidthavailability. In private delivery networks, the issue of bandwidthavailability for IPTV is often combated through the use of IPMulticasting. Considering the Internet is already believed to bebandwidth constrained, the use of multicasting could be deemeda requirement. The following paper will explore current issueswith deploying IPTV over the Internet, the use of multicast tocombat some of these problems, and the inherent challenges ofpushing multicast based IPTV services over the Internet