Integrated Logical Topology Design and Traffic Grooming in Re- Configurable WDM Networks

摘要

Wavelength-division multiplexing (WDM) networks provide reconfigurability and the possibility of creating single-hop communication channels between end nodes. This eliminates the electronic processing at intermediate nodes and reduces delay significantly. However, because of the limited number of network interfaces and other scalability issues, single-hop channels do not support all traffic demands. Some of the traffic requires routing or switching over multi-hop lightpaths to reach the destination. Such traffic is referred to as multi-hop traffic. The optimization of multi-hop traffic has significant impact on the performance of optical networks. In this paper, the authors propose an integrated logical topology design and traffic- grooming algorithm. The algorithm supports lightpath setup for multi-hop as well as single-hop paths. This is enabled by the consideration of the traffic grooming for multi-hop paths together with the logical topology design. They have used simulations with randomly generated traffic demand matrices to evaluate the performance of their algorithm in comparison with well-known algorithms such as HLDA, MMHA, and MRU. The results indicate that their algorithm performs better in terms of average weighted (logical) hop count and network throughput. In terms of average number of wavelengths per lightpath, its optical resource usage is similar to MMHA, more efficient than HLDA, but not as efficient as MRU.