The rotation counter protocol (RCP) is a token-passing ring protocol t
hat includes a special field called the rotation counter in the token.
It is capable of correlating the traffic among various stations and h
ence providing priority access. Not only is the mean delay of high-pri
ority traffic small and almost constant, but the delay jitter can also
be capped. In this respect, RCP can be used to serve synchronous traf
fic such as voice. By giving voice packets higher-priority access to t
he network, their real-time requirement can be satisfied in integrated
services. In this paper we evaluate the integrated-services performan
ce of RCP in terms of delay, jitter and throughput. Since this protoco
l can be adapted to the fibre-optic network, its performance is also c
ompared with that of FDDI. Our performance study demonstrates that RCP
-II is a potential candidate for high-speed token ring protocols.