the graph then the introduction chain is that path which has the greatest probability for success when one introduction chain fails at either task 604 or 606 telecommunications switch 101 re generates another introduction chain in an attempt to circumvent the obstacle and continues with it it will be clear to those skilled in the art after reading this specification how to generate the introduction chain from the directed graph and data in table 1 at task 603 telecommunications switch 101 establishes a communication event between the initiating user and the intermediary user during which the initiating user requests that the intermediary user contact the target user or next intermediary user in the introduction chain on behalf of the initiating user at task 604 telecommunications switch 101 either receives an indication that the intermediary user will in fact communicate with the target user or next intermediary user in the introduction chain on behalf of the initiating user or does not receive the indication this indication can be transmitted by either the initiating user or the intermediary user when telecommunications switch 101 does receive the indication control passes to task 605 otherwise control passes to task 602 where telecommunications switch 101 generates another introduction chain to circumvent to obstacle at task 605 telecommunications switch 101 establishes a communication event between the intermediary user and the target user or next intermediary user in the introduction chain during which the intermediary user requests that the target user or next intermediary user in the introduction chain communicate with the initiating user at task 606 telecommunications switch 101 either receives an indication that the target user will.