Duality between the Erlang loss system and a finite source queue

The paper provides a duality relation between an M/G/s/s queue and a GI/M/1/s/s queue. The M/G/s/s queue, so called the Erland loss system, has been extensively studied as a model of telephone exchanges. Using the duality relation and the previous results for the M/G/s/s queue, some well known and some new results can be derived for the GI/M/1/s/s queue that is useful model of multiple access systems such as time-sharing computer systems or multiple access communication channels.