L.Jereb, T. Jakab, F. Unghváry, ``Availability Analysis of Multi-Layer Optical Networks'', in Proceedings of OPTICOMM'00, Dallas, USA, Oct. 2000, pp. 303-314 [psfile]

The complexity of multi-layer resilience schemes and the high availability parameters provided by these methods require efficient availability analysis techniques, as well. In the paper the effectiveness of stratified sampling in availability analysis is demonstrated by the investigation of different protection strategies in SDH/SONET over WDM networks. The numerical results show that the application of stratified sampling results in sufficiently accurate estimation of the performance degradation with some hundreds of sample states even in the case of very efficient resilience schemes. \keywords{Optical networks, network reliability, statistical methods, stratified sampling}