On output processes of synchronization queues

We consider synchronization queues with finite or infinite buffers. There is one flow of tokens for each buffer. The input flow to each buffer, called a stream, is assumed to be a point process with finite intensity. Tokens arriving at each buffer have to wait to form a synchronized group and depart the system. We are concerned with output processes in this queue. The output processes of synchronization queues with some buffers having infinite capacities are studied. Further, we consider synchronization queues with two finite buffers and discuss the system state at output points in time. For these problems, some results that are already known are reviewed and some new results are introduced.