Analyse for optical access network with higher survivability

The survivability of optical access network was studied from the aspect of topology. On the basis of the early study from one new topology of access network with higher survivability, the Shared Risk Link Group (SRLG) concept is considered in analyzing survivability of the networks. The results showed the priority of the survivability of star-ring network with respect to other access topologies once more; an improved algorithm for calculation of network survivability was proposed. It decrease amount of network-state combination to be calculated and provides higher efficiency by way of calculate the combinations of each network layer separately and combine the equivalent network-state. The improve effect is better in larger total failure amounts.