In this paper, we present a variant of the Ethernet protocol that uses fibre optic media. By the use of periodic frames, the protocol caters to voice and data traffic, adapting to the number of voice calls. This protocol is thus suited for both office automation and industrial applications. We describe in detail how the proposed protocol can be implemented using inexpensive Ethernet VLSI chipsets with a little additional hardware. An extensive simulation study of the protocol shows that the framing imposes minimal additional overhead compared to the standard Ethernet. Under low loads, data delay is low while under heavy loads, voice performance is maintained at the expense of high data delays.