Book contents
- Frontmatter
- Contents
- Preface
- Acknowledgments
- 1 Optical networking technology
- 2 Design issues
- 3 Restoration approaches
- 4 p-cycle protection
- 5 Network operation
- 6 Managing large networks
- 7 Subgraph-based protection strategy
- 8 Managing multiple link failures
- 9 Traffic grooming in WDM networks
- 10 Gains of traffic grooming
- 11 Capacity fairness in grooming
- 12 Survivable traffic grooming
- 13 Static survivable grooming network design
- 14 Trunk-switched networks
- 15 Blocking in TSN
- 16 Validation of the TSN model
- 17 Performance of dynamic routing in WDM grooming networks
- 18 IP over WDM traffic grooming
- 19 Light trail architecture for grooming
- Appendix 1 Optical network components
- Appendix 2 Network design
- Appendix 3 Graph model for network
- Appendix 4 Graph algorithms
- Appendix 5 Routing algorithm
- Appendix 6 Network topology design
- References
- Index
9 - Traffic grooming in WDM networks
Published online by Cambridge University Press: 18 December 2009
- Frontmatter
- Contents
- Preface
- Acknowledgments
- 1 Optical networking technology
- 2 Design issues
- 3 Restoration approaches
- 4 p-cycle protection
- 5 Network operation
- 6 Managing large networks
- 7 Subgraph-based protection strategy
- 8 Managing multiple link failures
- 9 Traffic grooming in WDM networks
- 10 Gains of traffic grooming
- 11 Capacity fairness in grooming
- 12 Survivable traffic grooming
- 13 Static survivable grooming network design
- 14 Trunk-switched networks
- 15 Blocking in TSN
- 16 Validation of the TSN model
- 17 Performance of dynamic routing in WDM grooming networks
- 18 IP over WDM traffic grooming
- 19 Light trail architecture for grooming
- Appendix 1 Optical network components
- Appendix 2 Network design
- Appendix 3 Graph model for network
- Appendix 4 Graph algorithms
- Appendix 5 Routing algorithm
- Appendix 6 Network topology design
- References
- Index
Summary
Data traffic in ultra-long-haul WDM networks is usually characterized by large, homogeneous data flows, and metropolitan area WDM networks (MAN) have to deal with dynamic, heterogeneous service requirements. In such WAN and MAN networks, equipment costs increase if separate wavelengths are used for each individual service. Moreover while each wavelength offers a transmission capacity at gigabit per second rates (e.g., OC-48 or OC-192 and on to OC-768 in the future), users may request connections at rates that are lower than the full wavelength capacity. In addition, for networks of practical size, the number of available wavelengths is still lower by a few orders of magnitude than the number of source-to- destination connections that may be active at any given time. Hence, to make the network viable and cost-effective, it must be able to offer subwavelength level services and must be able to pack these services efficiently onto the wavelengths. These subwavelength services, henceforth referred to as low-rate traffic streams, can vary in range from, say, STS-1 (51.84 Mbit/s) capacity up to the full wavelength capacity. Such an act of multiplexing, demultiplexing, and switching of lower-rate traffic streams onto high-capacity lightpaths is referred to as traffic grooming. WDM networks offering such subwavelength low-rate services are referred to as WDM grooming networks. Efficient traffic grooming improves the wavelength utilization and reduces equipment costs.
In WDM grooming networks, each lightpath typically carries many multiplexed lower-rate traffic streams. Optical add–drop multiplexers (OADMs) add/drop the wavelength for which grooming is needed and electronic SONET-ADMs multiplex or demultiplex the traffic streams onto the wavelength.
- Type
- Chapter
- Information
- Survivability and Traffic Grooming in WDM Optical Networks , pp. 169 - 183Publisher: Cambridge University PressPrint publication year: 2006