Asons: an automatically switched optical networks simulator

Automatically switched optical networks (ASONs) are emerging as a primary technology choice for telecom operators' and service providers' optical backbone networks. Although the ITU-T has published a recommendation for ASONs, intensive research work is still going on towards specifying the ASON protocols, as well as mechanisms that could be implemented through them. Even though simulation is expedient towards evaluating and analyzing the performance of the emerging ASON protocols and algorithms, existing network simulators fail to support these operations. This paper presents work towards extending the ns-2 simulator with an additional simulation environment, namely asons, enabling experiments on ASON networks. The simulation environment was implemented as a set of distributed modules based on the G.8080 ITU-T recommendation. Special mechanisms focusing on ASON resilience features were realized and used to conduct a number of simulation experiments. Although the simulator is oriented to configuration and resilience experiments, it provides a sound basis for a rich set of other ASON experiments, with minimal additional customization effort. Following the presentation of the design and implementation aspects of the simulator, we describe sample resilience experiments supported by asons.