new path information to all nodes related to connection c step 140 before finishing step 150 if a non retracing connection cannot be established between node nk and nk 1 in step 120 processing continues by node nk determining whether a new non retracing connection can be established between node nk and node nk i step 160 in step 160 u201c i u201d is changed from 1 2 3 until i n k if a non retracing connection can be established between node nk and node nk i i is set to i step 170 the connection between node nk and node nk i is then set up step 180 as above processing then proceeds to propagate new path information to all nodes related to connection c step 140 before finishing step 150 a connection may not be able to be established between two nodes for a variety of reasons for example a network route may not exist between the two nodes alternatively an existing network route may not have additional capacity as current network traffic is already utilizing the route 39 s capacity also a failure may exist in the available network routes such failures may be caused by a physical break in a network.