When the multi-purpose selector of a node dialog box is set to Link Delay, you can view or enter a time-delay for each of the links going to the node. As soon as you set the selector to Link Delay, an additional selector will appear to the right of it. Each choice of the new selector will correspond to a link, and will be labeled with the link name if there is one, and/or the name of the parent node it comes from if the link is not disconnected.
The purpose of adding a link delay is for creating a dynamic Bayes net.
Note: You
can also set link delays by right-clicking
a selection
of links and choosing Delay.