  A queueing system handling a sequence of message arrivals is considered where
each message obsoletes all previous messages. The objective is to assess the
freshness of the latest message/information that has been successfully
transmitted, i.e., "age of information" (AoI). We study a variation of
traditional AoI, the "Relative AoI", here defined so as to account for the
presence of newly arrived messages/information to the queue to be transmitted.
