Implications of Implementing HDTV Over Digital Subscriber Line Networks

This thesis addresses the different challenges a telecommunications company would face when trying to implement an HDTV video service over a Digital Subscriber Line (DSL) connection. Each challenge is discussed in detail and a technology, protocol, or method is suggested to overcome that particular challenge. One of the biggest challenges is creating a network architecture that can provide enough bandwidth to support video over a network that was originally designed for voice traffic. The majority of the network connections to a customer premises in a telephony network consists of a copper pair. This type of connection is not optimal for high bandwidth services. This limitation can be overcome using Gigabit Ethernet (GE) over fiber in the core part of the network and VDSL2 in the access part of the network. For the purposes of this document, the core portion of the network is considered to be an area equal to several counties or approximately 50 miles in radius. The core network starts at the primary central office (CO) and spreads out to central offices in suburbs and small towns. The primary central office is a central point in the telecom operator\u27s network. Large trunks are propagated from the primary central office to smaller central offices making up the core network. The access portion of the network is considered to be an area within a suburb or small town from the central office to a subscriber\u27s home. Appendix A, located on page 60, contains a network diagram illustrating the scope of each of the different portions of the network. Considerations must also be given for the internal network to the residence such as category 5 (Cat5) cable or higher grade and network equipment that can provide up to 30 Megabits per second (Mbps) connections or throughput. The equipment in the telecommunications network also plays a part in meeting the challenge of 30 Mbps bandwidth. GE switches should be used with single mode fiber optic cable in the core part of the network. Digital Subscriber Line Access Multiplexers (DSLAM) with the capability to filter Internet Group Management Protocol (IGMP) messages should be used in the access part of the network to facilitate bandwidth utilization. Placement of this equipment and how the data is aggregated is another issue to consider when implementing HDTV service. Another major challenge facing the implementation of HDTV over DSL networks is controlling quality of service (QoS) throughout the network. Class of Service (CoS) and Differentiated Services (DiffServ) is a method of QoS that would enable video packets to have a higher priority and less delay than other data packets. The consumer could have data, video, and voice traffic all over the same DSL connection. Data, video and voice packets would need to have a different priority in order to maintain appropriate QoS levels for each service. The use of advanced technology in video encoding will be essential to the success of the video service. MPEG-2, MPEG-4, and Windows Media 9 are just a few of the video encoding technologies that could be used to reduce the necessary bandwidth for HDTV. The advancement of this technology is essential to allow telecommunications providers to offer HDTV. Another challenge for the telecom operator concerns the security of the network and service after implementation. Theft of service will be another area that the telecomm operator will be forced to resolve. The cable operators currently face this issue and lose millions of dollars in revenue. Authentication, IP filtering and MAC address blocking are a few possible solutions to this problem

ULE Robust Header Compression For Ip-Based Communication Over Digital Video Broadcasting-Satellite (DVB-S) [TK5104. T261 2008 f rb].

Untuk selama 35 tahun, Internet telah berkembang dan bertumbuh dengan pesat. Disebabkan pembangunan yang mendadak, permintaan capaian Internet menjadi kian popular di mana-mana saja melalui pelbagai jenis media, Over a span of thirty five years, the Internet has developed and grown rapidly. Due to its rapid growth, the demand for Internet access today is everywhere and over every possible medium such as satellite communications

DSL-based triple-play services

This research examines the triple play service based on the ADSL technology. The voice over IP will be checked and combined with the internet data by two monitoring programs in order to examine the performance that this service offers and then will be compared with the usual method of internet connection.This research examines the triple play service based on the ADSL technology. The voice over IP will be checked and combined with the internet data by two monitoring programs in order to examine the performance that this service offers and then will be compared with the usual method of internet connection.

Validation of "triple-play" services in the access node

Mestrado em Engenharia Electrónica e TelecomunicaçõesCom o grande crescimento das comunicações fixas, as tecnologias de fornecimento de acesso à Internet, como o cabo (CATV) e o par de cobre (xDSL), têm possibilitado o fornecimento de serviços adicionais para além do típico acesso à Internet de Banda Larga (em que, desde há vários anos o serviço de televisão já existe na tecnologia de cabo). Assim sendo, e ainda devido a uma forte concorrência entre operadores de cabo e de “cobre”, o DSL Forum apresenta uma solução de arquitectura da rede de acesso e agregação que permite a migração da tradicional tecnologia ATM para Ethernet, em tecnologias baseadas em xDSL. A migração da arquitectura para uma rede baseada em Ethernet permite o fornecimento de serviços adicionais que exijam altos débitos, qualidade de serviço, transmissão de multicast, VOIP, entre outros. A presente tese apresenta os requisitos propostos pelo DSL Forum para o equipamento da rede de acesso e agregação: o nó de acesso (DSLAM), e um conjunto de testes conducentes à validação dos mesmos em laboratório, simulando uma possível rede de fornecedor de serviços. ABSTRACT: With the large growth of fixed communications, the technology that provides Internet access, such as cable (CATV) and copper (xDSL), need to enable the provision of additional services beyond the typical broadband Internet access (where, television service already exists for several years over cable technology). Thus, because of strong competition between cable and copper operators , DSL Forum presents an architecture and aggregation solution for the xDSL based access networks that allows the migration of traditional ATM technology to Ethernet. The migration of the architecture to Ethernet based network is due to the high speeds offer, and the possibility of additional services supporting quality of service, multicast transmission, VOIP, amongst others. This thesis presents the requirements proposed by the DSL Forum for the equipment of the access network and aggregation: access node (DSLAM), and their validation in a laboratory environment, simulating service provision scenarios

Novel algorithms for fair bandwidth sharing on counter rotating rings

Rings are often preferred technology for networks as ring networks can virtually create fully connected mesh networks efficiently and they are also easy to manage. However, providing fair service to all the stations on the ring is not always easy to achieve. In order to capitalize on the advantages of ring networks, new buffer insertion techniques, such as Spatial Reuse Protocol (SRP), were introduced in early 2000s. As a result, a new standard known as IEEE 802.17 Resilient Packet Ring was defined in 2004 by the IEEE Resilient Packet Ring (RPR) Working Group. Since then two addenda have been introduced; namely, IEEE 802.17a and IEEE 802.17b in 2006 and 2010, respectively. During this standardization process, weighted fairness and queue management schemes were proposed to be used in the standard. As shown in this dissertation, these schemes can be applied to solve the fairness issues noted widely in the research community as radical changes are not practical to introduce within the context of a standard. In this dissertation, the weighted fairness aspects of IEEE 802.17 RPR (in the aggressive mode of operation) are studied; various properties are demonstrated and observed via network simulations, and additional improvements are suggested. These aspects have not been well studied until now, and can be used to alleviate some of the issues observed in the fairness algorithm under some scenarios. Also, this dissertation focuses on the RPR Medium Access Control (MAC) Client implementation of the IEEE 802.17 RPR MAC in the aggressive mode of operation and introduces a new active queue management scheme for ring networks that achieves higher overall utilization of the ring bandwidth with simpler and less expensive implementation than the generic implementation provided in the standard. The two schemes introduced in this dissertation provide performance comparable to the per destination queuing implementation, which yields the best achievable performance at the expense of the cost of implementation. In addition, till now the requirements for sizing secondary transit queue of IEEE 802.17 RPR stations (in the aggressive mode of operation) have not been properly investigated. The analysis and suggested improvements presented in this dissertation are then supported by performance evaluation results and theoretical calculations. Last, but not least, the impact of using different capacity links on the same ring has not been investigated before from the ring utilization and fairness points of view. This dissertation also investigates utilizing different capacity links in RPR and proposes a mechanism to support the same

Lambda-Based Prioritisation In Multichannel Optical Ip Network

The explosion of the Internet and its application creates demand for more network resources and bandwidth. The internet traffics such as voice, video and interactive applications are more susceptible to delay and jitter while bursty data traffic such as e-mail and file transfer are more sensitive to loss. To accommodate the bandwidth demands, the trend of the network also experiences a major change from copper-based to optical fibre transmission link. Besides of its many superior properties, optical fibre has an extraordinary limitless bandwidth. However increasing the bandwidth in respond to the need of bandwidth demands is not necessarily an appropriate solution. As more and more applications use the bandwidth, congestion still occurs. Therefore, the Quality of Service (QoS) is introduced into the network. Different type of Internet traffic requires different treatment while propagating along the network and thus requires a specific QoS characteristic.In this research, the traffic is split into four levels of priority classes that require different levels of QoS treatment. Each class of traffic is transmitted at different wavelength (A). The highest priority class deserved the best QoS treatment while lower prichity classes needs the lower QoS treatment. Therefore, there are four channels to carr four types of traffic. The Sub-Carrier Modulation (SCM) technique is used to cal the optical traffic and it is transmitted on to the optical communication ink using Wavelength Division Multiplexing (WDM) technology. The Fib( Delay Line (FDL) that acts as an optical buffer is used to resolve the contention on the input port at the receiver. During the contention resolution, the lower priority traffic is buffered while transmitting the higher priority traffic. The simulation results show that the highest priority traffic gets the best treatment while propagating in the network. The performance of the highest priority traffic is the best whereby it has low loss, low delay and yet high throughput and efficiency. The lower priority traffic sustains high loss, longer delay but low throughput and efficiency

Mpls/Vpls: servicio de Lan privada virtual sobre Mpls

En la actualidad MPLS se ha convertido en una de las soluciones más apetecidas para la implementación del transporte en Backbones metropolitanos, las ventajas de una red Multiservicio sobre una red IP son innumerables entre ellas están la implementación de soluciones Ethernet punto a punto en las cuales dos equipos remotos pueden compartir el mismo dominio de broadcast; en estos momentos se esta trabajando en la implementación de VPNs de nivel 2 que permitan solucionar el problema de la conversión de direcciones MAC a IP. Dentro de los antecedentes de las investigaciones sobre la emulación de redes LAN en Backbones, encontramos ATM LANE que emulaba una LAN sobre una WAN ATM, el servicio ATM LANE tenía 4 componentes básicos. Un LEC (Lan Emulation Client), un LECS (Lan Emulation Configuration Server), un LES (Lan Emulation Server) y un BUS (Broadcast Unknow Server), estos componentes interactúan Emulando una LAN en la cual los LEC comparten un mismo dominio de Broadcast; otro antecedente importante tiene que ver con AAL5 y con su mecanismo “LLC Encapsulation” que multiplexa varios protocolos sobre un mismo circuito virtual. Cuando se habla de VPLS es de vital importancia hacer un repaso por los conceptos más importantes de MPLS, explicar como opera el Backbone MPLS con todos sus componentes entre ellos los LSR (Label Switching Router), como se realiza el intercambio de etiquetas y como este intercambio de etiquetas optimiza el envío de paquetes en la re

Aperfeiçoamento do desempenho do TCP em links assimétricos via políticas de escalonamento de filas

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência da Computação.O objetivo deste trabalho é apresentar uma proposta de melhoria a problemas de desempenho do TCP, que ocorrem devido aos efeitos da assimetria. Estes problemas acontecem em redes de acesso assimétricas, causando degradação no desempenho final do TCP, os quais ocorrem devido as imperfeições e variações no retorno dos pacotes de confirmação, Acknowlegement, enviados pela estação cliente em resposta aos pacotes de dados recebidos da estação servidora. Este trabalho detalha algumas soluções a este problema, os quais usam técnicas locais de camada de rede. Como resultado de nossa pesquisa apresentamos uma proposta baseada no aperfeiçoamento e combinação de algumas destas técnicas, e cujos resultados obtidos analisamos através de simulação de modelos

Desarrollo de aplicaciones basadas en network processors

Escueal Técnica Superior de Ingeniería de Telecomunicació