Elastic Lambda Aggregation Network Research Articles

Novel Automatic Service Restoration Technique by Using Self-Reconfiguration of Network Resources for a Disaster-struck Metro-Access Network

This paper shows the concept of the elastic lambda aggregation network (EλAN) that will achieve an elastic common access infrastructure for the metro-access network. It proposes a service restoration technique that uses optical path switching and intercentral office handover for EλAN to recover from disasters. The feasibility of the proposed service restoration technique is successfully demonstrated for the first time by using a prototype testbed of a metro-access network. By applying both orthogonal frequency division multiplexing and adaptive modulation, the system automatically changes the transmission parameters (modulation level, the number of subcarriers, and symbol rate) according to the service requirements and conditions of the optical distribution network, such as the link's end-to-end optical loss, in order to achieve accommodate multiple services. In the experiment, an optical network unit in a faulted system automatically reconnected within 10 s to another office 20-km away with the same throughput.

Experimental evaluation of fault recovery methods in Elastic Lambda Aggregation Network

Experimental evaluation of fault recovery methods in Elastic Lambda Aggregation Network

Time estimation of logical optical line terminal migration for Elastic Lambda Aggregation Network

Elastic Lambda Aggregation Network (EλAN), the next-generation access and aggregation integrated network, has been proposed. In EλAN, Optical Line Terminals (OLTs) are programmable, and Logical-OLTs (L-OLTs) can be migrated between different P-OLTs. L-OLT migration leads to enhance failure resistance and improve power saving. We have experimented L-OLT migration between P-OLTs in our laboratory. However it is necessary to evaluate how L-OLT migration time changes according to physical distance. Therefore we made an experiment of L-OLT migration in wide area network on JGN-X. This paper proposes estimation equation of L-OLT migration time. The equation leads to determine L-OLT arrangements considering time of L-OLT migration for physical distance.

Logical Optical Line Terminal Placement Optimization in the Elastic Lambda Aggregation Network With Optical Distribution Network Constraints

The elastic lambda aggregation network (EλAN) has been presented as an access/aggregation integrated network that can accommodate multiple network services. In the EλAN, optical line terminals (OLTs) become programmable and configure logical OLTs (L-OLTs) to support network services that have different protocols and quality of service requirements. To achieve the flexible utilization of network resources and improve energy efficiency, L-OLTs are migrated between programmable OLTs like virtual machines. In this paper, an integer linear programming (ILP) model of the L-OLT placement optimization problem with optical distribution network constraints is presented. Based on this ILP model, the communication suspension time that occurs with L-OLT migration is investigated. We discuss the modification of the L-OLT migration sequence to reduce the communication suspension time. The impact of the modification on the energy saving effect of L-OLT placement optimization is evaluated in this paper.