Broadband Network Architectures: Designing and Deploying Triple-Play Services: Designing and Deploying Triple-Play Services - Softcover

Hellberg, Chris

Softcover

ISBN 10: 0132300575 ISBN 13: 9780132300575

Publisher: Prentice Hall, 2007

Synopsis

“Network professionals who are looking to deploy triple-play service provider networks will find this book a useful tool.”

–Michael Newbery, IP Architect, TelstraClear Limited

 

“This book provides a wealth of information on current and future broadband architectures, services, and deployments. It will serve both experienced technical experts needing a comprehensive reference, as well as those needing a concise explanation of broadband access architectures and multi-play services.”

–Sanjay Wadhwa, Product Line Manager, IP Edge Products, Juniper Networks

 

“This book is a thorough guide for anyone involved with triple-play networks. Its multivendor approach and references to the latest standards from the DSL Forum and the IETF makes it a must-have for anyone involved in broadband access networks.”

–Andrea Lasagna, Data & Video Services Manager, FASTWEB

 

Service providers are increasingly focused on delivering triple-play bundles that incorporate Internet, video, and VoIP services–as well as multi-play bundles containing even more advanced services. Broadband Network Architectures is the first comprehensive guide to designing, implementing, and managing the networks that make triple-play services possible.

 

Hellberg, Greene, and Boyes present their field-tested industry best practices and objectively evaluate the tradeoffs associated with key up-front architectural decisions that balance the complexities of bundled services and sophisticated traffic policies. Broadband Network Architectures not only documents what is possible on this rapidly changing field of networking, but it also details how to divide Internet access into these more sophisticated services with specialized Quality of Service handling.

 

Coverage includes 

·    An in-depth introduction to next-generation triple-play services: components, integration, and business connectivity

·    Triple-play backbone design: MPLS, Layer 3 VPNs, and Broadband Network Gateways (BNGs)/Broadband Remote Access Servers (B-RAS)

·    Protocols and strategies for integrating BNGs into robust triple-play networks

·    Triple-play access network design: DSLAM architectures, aggregation networks, transport, and Layer 2 tunneling

·    VLAN-per-customer versus service-per-VLAN architectures: advantages and disadvantages

·    PPP or DHCP: choosing the right access protocol

·    Issues associated with operating in wholesale, unbundled environments

·    IP addressing and subscriber session management

·    Broadband network security, including Denial of Service attacks and VoIP privacy

·    The future of wireless broadband: IMS, SIP, and non-SIP based fixed mobile convergence and wireless video

 

Contents

Foreword 

Preface 

About the Authors 

Chapter 1          A History of Broadband Networks 

Chapter 2          Next Generation Triple-Play Services 

Chapter 3          Designing a Triple-Play Backbone 

Chapter 4          Designing a Triple-Play Access Network

Chapter 5          Choosing the Right Access Protocol

Chapter 6          Evolutions in Last Mile Broadband Access 

Chapter 7          Wholesale Broadband Networks

Chapter 8          Deploying Quality of Service 

Chapter 9          The Future of Wireless Broadband 

Chapter 10        Managing IP Addressing 

Chapter 11        Dynamic User Session Control

Chapter 12        Security in Broadband Networks 

 

Appendix A       Glossary of Acronyms and Key Terms 

Appendix B       Glossary of Packet Diagrams 

Index 

 

 

About this title

About the Author

Chris Hellberg has been working in the data communications industry for the last seven years for both telcos and vendors. He has design and operational experience with providers in Asia-Pacific and the EMEA region. He is currently a Professional Services Consultant for Juniper Networks in the EMEA region, specializing in BRAS and core platforms. His role with Juniper is to assist customers with the design, test, build, and deployment phases of broadband access and backbone networks of all sizes. He lives in the United Kingdom, although he most often can be found in one of Europe’s many airports.

Dylan Greene is a consultant with the Juniper Networks Professional Services group. He has more than a decade of technical networking experience, having worked in a variety of environments from Tier 1 carriers, greenfield providers, financial enterprise networks, and mobile carriers to aerospace and defense projects. His primary expertise is in designing and deploying IP and MPLS networks, with a subfocus on network security. Prior to Juniper Networks, his work included academic computing, helping to establish an early competitive regional ISP/DSL provider, a managed IDC/hosting provider, and working on large, multinational financial networks. He has been based in Asia-Pacific, Europe, and North America, and currently resides in Boston with his wife, Luciana.

Truman Boyes has designed and implemented large-scale carrier networks for the past ten years. He is a Professional Services Consultant for Juniper Networks in Asia-Pacific, where he is implementing next-generation networks that cater to larger subscriber growth and provide resiliency. He has designed networks all over the world that specialize in MPLS, Quality of Service, and advances in traffic engineering. He is active in numerous Internet and security-related technical forums. He lives with his partner in Wellington, New Zealand.

 

Excerpt. © Reprinted by permission. All rights reserved.

Extreme Programming Installed

Preface

When ADSL hit the market in the late 90s, the residential broadband market started to really heat up. Dial-up Internet access, while being a well-understood and reliable service, could not keep pace with the demands of having homes connected at broadband speeds. Cable networks, with their hybrid fiber and coax networks, were also competing for similar customers as traditional Telcos. Thanks to cable operators, Triple Play services had already gained a foothold in the customer conscience as a service bundle that can be provided by a single company. This eased the way for Telcos to also deliver their own Triple Play service bundles over a single copper pair—the same copper pair that was used for many years as a simple telephone line.

A Triple Play package is a bundle of an Internet, video, and VoIP service. Video services almost always have two components: a Video on Demand, and an IP Television (IPTV). IPTV takes traditional terrestrial and satellite channels and delivers them over an IP network to the customer premises. Multi-Play services are an extension of this concept and divide Internet access in to more sophisticated services with specialized Quality of Service handling.

Until the early to mid part of this decade, apart from some early-adopters, service providers were not given to broadening their residential data portfolio past Internet access. This mindset is rapidly changing and the market is diverging into two segments. The first segment is the commodity ISPs, who provide a cheap and fast Internet service. The cost-barrier to entry is lower due to the lower service overhead; the competition here is fierce. The second is to whom this book is aimed—those providers in, or looking at, getting into the Triple- and Multi-Play service market.

Several reasons drive the diversification. From a political perspective, many Telcos with wired access are finding their traditional revenues being eroded due to regulatory pressures. Triple- and Multi-service bundles are an ideal way to maintain some service margin in an increasingly competitive market. For access seekers, regulatory intervention is a much cheaper way to expand network coverage compared to an expensive copper or fiber access network rollout. For both wholesalers and access seekers, there was a major drawback to video service deployment: ADSL does not have much bandwidth to play with. ADSL2+ pushes up the downstream limit to over 24Mbps, giving ample headroom for high-definition IPTV channels, while not making a severe impact on Internet performance.

This book is the perfect companion for anyone in the networking industry. If you are a journalist or analyst who wants more inside, in-depth information about next-generation broadband access networks, you will find it here. Or if you work at a vendor or service provider, the architectures and configurations enhance your technical understanding with practical applications of protocols and hardware.

ATM-based DSL networks are well understood and have been in the marketplace for many years. There already one or two books on these broadband networks. However, this book fills the gap in the market for a leading-edge architecture guide of next-generation, Ethernet-based DSL networks and Triple- and Multi-Play services. Because this book is more about architectures than focusing exclusively on technology, this book appeals to a wider audience than just technicians. Planners, financial controllers, managers, and network architects will also find useful information. The designs and techniques described in this book apply to many markets around the world.

The intent of this book is to inform the reader of best practices in the industry and where there is still contention, the pros and cons of each alternative are laid out. For example, North American providers generally choose to go with a customer-specific VLAN architecture, whereas European providers prefer to use a service VLAN. Explanations of these terms and the advantages and disadvantages of each are two examples of the flexible approach that this book attempts to provide.

Many readers already in the industry will be familiar with the topics in each chapter, but the concepts in the latter parts of each chapter are not intended for beginners. For example, many of the MPLS concepts in Chapter 3, "Designing a Triple Play Backbone," are not intended for those whose exposure to MPLS is for the first time. The description for each of the 12 chapters listed in the next section tells the reader the intended technical level along with any recommended reading titles.

What You Will Learn

After reading this book, the reader will have enough knowledge to work through the issues and challenges involved with designing and deploying a triple- and multi-play network. There may be times where there is not enough detail in a particular section. The intention has been to cover at least the basics, so the reader at least knows what issues are involved if they need to do more research. Most of the IETF RFC-based technologies have been referenced by URL for further investigation. Although Wikipedia might not be 100% accurate, for technical information, it is a reliable and useful resource for unfamiliar topics. As of January 2007, PDFs of in-force ITU-T specifications are freely downloadable. These are quite specific in nature and are good when needing to delve deep in to specific aspects of a DSL modulation or Ethernet protocol.

Chapters of This Book

Chapter 1, "A History of Broadband Networks," describes the beginnings of broadband access networks, starting with the advent of the DSL family of technologies—CAP and DMT—and how this had an effect on deployment throughout the world. This tells the story of technology development from vendors and deployment milestones by service providers. There are also discussions of broadband access devices, access protocols, and the most common authentication and accounting protocol—RADIUS. The technical knowledge needed to understand this chapter is low.

Chapter 2, "Next-Generation Triple-Play Services," is an introduction to what triple- and multi-play services really mean. What does a video service actually entail? What are the components of a triple-play network, from a high-level perspective? How is VoIP integrated into the network? These questions are all answered in this chapter. There is also a section on business connectivity, describing how services such as Layer 3 and Layer 2 VPNs are being deployed with DSL access. The technical knowledge in this section is medium due to heavy use of jargon and some of the more complex topics in each subsection.

Chapter 3, "Designing a Triple-Play Backbone," looks at how operators are implementing backbones that can carry triple-play services. The chapter begins with an overview of the most popular type of protocol on provider backbones: Multi-Protocol Label Switching (MPLS). The discussion quickly moves to describing a common service that providers have implemented—Layer 3 VPNs. MPLS networks are also used for their traffic engineering properties, and may not use any Layer 3 VPNs except for business services. Included are many examples of how IP multicast services can be integrated into these networks. The discussion starts from a common example of multicast and Protocol Independent Multicast (PIM) and how traffic and protocols flow. There are many optimizations and enhancements possible with this model, such as using source-specific multicast and redundant rendezvous points, which are described here. An efficient way to transport multicast on an MPLS network using point-to-multipoint LSPs are explained in detail here. Also included is a look to the future of next-generation backbone IPTV delivery using VPLS with point-to-multipoint trees.

The Broadband Network Gateway (BNG), often called a Broadband Remote Access Server (B-RAS), is an important point for service definition. The focus moves to integrating BNGs in to the network for triple-play services. This covers multicast protocols on the BNG, such as IGMP and additional features for PIM. Finally, implementing a highly available core network is a hallmark of any service provider, so there are protocols and strategies, such as BFD fast-reroute, that can be added to a network for added robustness.

The technical knowledge required for this chapter is medium to advanced because many of the principles described assume some prior experience with MPLS networks and multicast protocols.

Chapter 4, "Designing a Triple-Play Access Network," covers one of the most important aspects of a next-generation DSL network—the access network. There are two major components to this critical piece of infrastructure: the DSLAM, and the network between the DSLAM and the BNG, also called the aggregation network. DSLAM deployment architectures such as hub-and-spoke, daisy-chained are shown here. Designing the aggregation network is an important task. Examples described in Chapter 4 are using an MPLS network to transport customer traffic from DSLAMs to the BNG. Layer 2 tunneling technologies, such as VPLS, Martini or Kompella VPNs. Extensive deployment scenarios of these technologies is also shown as more traditional transport, such as CWDM, DWDM, or dark fiber.

The second part to the chapter is the lively discussion as to the type of VLAN architecture to run between the DSLAM and the BNG: Should it be a 1:1, VLAN-per-customer model, or a service-per-VLAN model? The type of model chosen has important implications and should be designed correctly from the start. This chapter contains important information to enable the reader to make an informed decision for their VLAN architecture. Medium-level technical knowledge of MPLS protocols is also recommended for this chapter.

Chapter 5, "Choosing the Right Access Protocol," covers an equally lively debate in the industry—whether to use PPP or DHCP as the protocol between the BNG and the customer. Jargon and protocols, deployment scenarios are explained here. As with any architectural choice in this book that does not have a clear answer, there are pros and cons of both approaches. Despite being quite narrow in focus, a low to medium level technical knowledge of PPP and DHCP is needed for this chapter.

Chapter 6, "Evolutions in Last-Mile Broadband Access," is a chapter for those who like to get deep into technical details on transport networks. This chapter takes a tour of the evolution of DSL networks, from the first ADSL deployments using Carrierless Amplitude/Phase Modulation to the standard Discrete Multi-Tone (DMT) in use today. Topics commonly associated with DSL lines—spectrum usage, cross-talk, special protocol features, and data rates—are explained in detail in this chapter. Line-level protocols that are covered include ADSL, ADSL2, ADSL2+, VDSL, VDSL2+, and SHDSL. This chapter is appropriate for anyone with a medium-level knowledge of transport protocols.

Chapter 7, "Wholesale Broadband Networks," covers what wholesale providers and access seekers need to know when working in a wholesale, unbundled environment. An unbundled environment is one where a local authority has mandated that an incumbent provide access to customers connected to the local loop. Types of unbundled services range from a simple Layer 3 IP wholesale service to a full unbundled copper service, which are two such examples that are covered. Some additional attributes and protocols associated with L2TP, such as tunnel fragmentation and proxy LCP, are also covered here. Low to medium level knowledge of L2TP and prior reading of Chapter 4 are sufficient for this chapter.

Chapter 8, "Deploying Quality of Service." Not a day goes by in discussions of next-generation DSL services without mentioning Quality of Service. This substantial topic is all about how to effectively deliver multiple services in a bandwidth-constrained environment. This covers the history of QoS in an IP environment, showing how IP precedence and Differentiated Services have had an important impact in helping to define a prioritization architecture. Uses of these mechanisms with QoS features, such as rate-limiting, shaping, RED and W-RED, and strict priority scheduling are a few of the features explained in this chapter. The concepts in this chapter do not require much prior knowledge and a low to medium level of understanding of access architectures in Chapter 4.

Chapter 9, "The Future of Wireless Broadband," presents a survey of the wireless technologies that complement today's traditionally wireline-based multi-service networks. With advances in 3G wireless technologies such as growing data rates, advanced in service control, security & quality of service, it's becoming possible to deliver comparable services wirelessly as it is over wireline triple & quad-play architectures. The chapter covers the history of wireless data, from the ETSI GSM and early CDMA days, through Wideband CDMA & UMTS, through today's evolving wireless broadband architectures, such as IMS, SIP, and non-SIP based fixed mobile convergence and wireless video. The chapter contains a survey of the different technologies, network architectures behind them, and evolving wireless broadband standards.

Chapter 10, "Managing IP Addressing," takes a look at one of the simpler tasks of a BNG—assigning an IP address. This chapter explains all the options available to a network operator, for both PPP- and DHCP-based networks. Whether this involves simple static address assigned via RADISU or a more complex approach using dynamically signaled on-demand address pools (ODAP), many common approaches are described in this chapter. Keeping with the forward thinking trend of this book, there is also a section on the implications of IP address management in an IPv6 access network. The concepts in this chapter are of a low to medium technical complexity.

Chapter 11...

Edition details

• Publisher: Prentice Hall
• Publication date: 2007
• ISBN 10: 0132300575
• ISBN 13: 9780132300575
• Binding: Paperback
• Language: English
• Edition number: 1
• Number of pages: 600