A method for automatically routing and switching a connection in an automatically reconfigurable WDM network, comprising: receiving a request to connect a source node with a destination node; identifying a plurality of viable regenerator paths between said source and destination nodes, based on constraints in said request and on current network configuration and loading; and selecting a best path from said plurality of viable regenerator paths to serve said connection, wherein said step of identifying comprises: constructing 'n' valid link paths for connecting said source node and said destination node based on the constraints in said request and on the current network configuration and loading; and for each valid link path, configuring up to 'm' groups of viable regenerator paths corresponding to a respective associated valid link path, based on current regenerator availability data and operational parameters of said regenerators, wherein 'n' and 'm' are integers selected for said WDM network, wherein said step of configuring up to 'm' groups of viable regenerator paths comprises: collecting regenerator availability data; constructing said viable regenerator paths including a regenerator at 'k' nodes along said associated link path; and grouping said viable regenerator paths according to the number 'k' of regenerators and selecting the best viable regenerator path of each group based on an estimated Q quality factor and a cost function of each path in the group, wherein 'k' is an integer between 0 and the number of intermediate nodes along said associated link path, wherein said step of selecting a best path from said plurality of viable regenerator paths comprises sorting said viable regenerator paths based on an estimated performance parameter, wherein said estimated performance parameter is one of an estimated Q, a cost function or both said estimated Q and said cost function. receiving a request to connect a source node with a destination node; identifying a plurality of viable regenerator paths between said source and destination nodes, based on constraints in said request and on current network configuration and loading; and selecting a best path from said plurality of viable regenerator paths to serve said connection, wherein said step of identifying comprises: constructing 'n' valid link paths for connecting said source node and said destination node based on the constraints in said request and on the current network configuration and loading; and for each valid link path, configuring up to 'm' groups of viable regenerator paths corresponding to a respective associated valid link path, based on current regenerator availability data and operational parameters of said regenerators, wherein 'n' and 'm' are integers selected for said WDM network, wherein said step of configuring up to 'm' groups of viable regenerator paths comprises: collecting regenerator availability data; constructing said viable regenerator paths including a regenerator at 'k' nodes along said associated link path; and grouping said viable regenerator paths according to the number 'k' of regenerators and selecting the best viable regenerator path of each group based on an estimated Q quality factor and a cost function of each path in the group, wherein 'k' is an integer between 0 and the number of intermediate nodes along said associated link path, wherein said step of selecting a best path from said plurality of viable regenerator paths comprises sorting said viable regenerator paths based on an estimated performance parameter, wherein said estimated performance parameter is one of an estimated Q, a cost function or both said estimated Q and said cost function. constructing 'n' valid link paths for connecting said source node and said destination node based on the constraints in said request and on the current network configuration and loading; and for each valid link path, configuring up to 'm' groups of viable regenerator paths corresponding to a respective associated valid link path, based on current regenerator availability data and operational parameters of said regenerators, wherein 'n' and 'm' are integers selected for said WDM network, wherein said step of configuring up to 'm' groups of viable regenerator paths comprises: collecting regenerator availability data; constructing said viable regenerator paths including a regenerator at 'k' nodes along said associated link path; and grouping said viable regenerator paths according to the number 'k' of regenerators and selecting the best viable regenerator path of each group based on an estimated Q quality factor and a cost function of each path in the group, wherein 'k' is an integer between 0 and the number of intermediate nodes along said associated link path, collecting regenerator availability data; constructing said viable regenerator paths including a regenerator at 'k' nodes along said associated link path; and grouping said viable regenerator paths according to the number 'k' of regenerators and selecting the best viable regenerator path of each group based on an estimated Q quality factor and a cost function of each path in the group, wherein 'k' is an integer between 0 and the number of intermediate nodes along said associated link path, wherein said step of selecting a best path from said plurality of viable regenerator paths comprises sorting said viable regenerator paths based on an estimated performance parameter, wherein said estimated performance parameter is one of an estimated Q, a cost function or both said estimated Q and said cost function.