To keep pace with the trend of service diversity in communication, providing differentiated reliability services become a focus topic of WDM networking. While the wavelength has transmission capacity at gigabit per second rates, the network may be required to support traffic connections at much lower rates than the full wavelength capacity. In addition, for networks of practical size, the number of available wavelengths is still much lower than that of source to destination connections requests. Thus the solution lies in efficiently grooming the low rate traffics onto the wavelength channels. Traffic grooming can aggregate low-rate connections onto high-capacity wavelength channels, also called lightpaths, to make efficient use of the wavelength capacity. Considering both the survivability for differentiated reliability services and traffic grooming, a differentiated shared protection algorithm called PSPTG, which means Partial Shared-path Protection algorithm supporting Traffic Grooming, is proposed. In this algorithm, a shared protection scheme of partial lightpath based on link reliability is presented to meet the requirements of reliability and bandwidth of connections. Simulation results show that the algorithm is efficient in terms of resources utilization by routing more connections.
Efficiently grooming low-rate traffic flows into high-capacity lightpaths will improve the network throughput and resource utilization. In this paper, we study the traffic -grooming algorithm for WDM mesh networks. A novel dynamic grooming graph is proposed, which models the number of transceivers per node and the number of wavelength per fiber in addition to the combined information of IP layer and WDM layer, while taking into account the constraints of wavelength continuity in optical domain. Based on the grooming graph, a new dynamic traffic-grooming algorithm, namely Integrated Grooming Algorithm (IGA), is developed to provide an efficient solution to the traffic-grooming problem in WDM optical mesh networks. This algorithm is evaluated via simulations and results reveal that satisfactory performance of the proposed algorithms can be achieved.
Optical fiber links, due to sharing some common physical resources, e.g., fiber cable, conduit and Right of Way, have certain failure-dependent. The term "Shared Risk Link Groups (SRLG)" is introduced to describe the relationship between links with shared risk; SRLG diversity has become the important constraint of protection design problem. This paper addresses SRLG-constraint-based shared-path protection design problem with differentiated reliability. Via
SRLG conditional failure probability concept, we propose an efficient PSD-SPP (Partial SRLG-disjoint Shared-Path Protection) algorithm to solve the protection design problem with differentiated reliability under the consideration of links failure-dependence. Simulation result shows that this algorithm not only efficiently satisfies the user-specific requirement, but also effectively decreases the network-blocking ratio.
In WDM networks, the bandwidth request of a traffic stream is usually much lower than the capacity of a wavelength. Traffic grooming can aggregate low-rate connections onto high-capacity lightpaths to make efficient use of the bandwidth. But most of the researches related to traffic grooming focused on ring networks, and fewer concerns are about the dependable traffic grooming of low-rate connections in WDM mesh networks. In our study, we present a Hamiltonian Cycle Protection based Traffic Grooming algorithm (HCPTG) considering both the survivability and traffic grooming in WDM mesh networks. Simulation results show that good performance can be achieved in terms of capacity efficiency.