Abstract
The problem of service time-varying traffic in flexible transparent optical networks, assuming that the incoming connections and their duration are not known in advance, is considered in this work. Time-varying traffic requires dynamic spectrum allocation for connections implemented in the network. In the considered problem, a path with the required spectrum around the reference frequency is determined for each incoming connection by the routing algorithm. In order to take into account the dynamic spectrum allocation for the connections in the network, two spectrum expansion/- contraction schemes have been applied on the basis of which the average blocking probability for the incoming request additional slot was determined.