General availability model for multilayer transport networks

This paper reports the initiative taken within the IST-project NOBEL to define a general availability model and collect general availability numbers for several network equipment types, independent from vendor specific product information. The model includes optical layer equipment as well as IP and SDH equipment, described using a triplet-representation for each of the availability measures with optimistic, nominal and conservative values. The availability model has been applied to different typical transport network scenarios. Several case studies were performed to compare the end-to-end connection availability and the required network capacity for different resilience mechanisms.