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In this paper two protocols integrating voice and data on a token bus LAN are proposed. These protocols use the access mechanism of the Token Bus protocol, but in addition the token bypasses idle stations, exploiting the periodicity of voice. The priority scheme of the Token Bus is used to separate voice traffic from data traffic. Voice packets are assigned to the higher priority while data packets and the voice call packets for setting up calls are assigned to the lower priority. The proposed protocols were studied via simulation tools. The simulation results show that these protocols satisfy the delay constraint of voice traffic, and at the same time, guarantee a sufficient bandwidth for data traffic. Results obtained under various traffic conditions are given.

This paper presents a modified token ring LAN, called the Scheduling Bypass Periods Network (SBP-Net). SBP-Net uses the ring to implement the IEEE 802.5 standard token ring functions and an auxiliary bus for control purposes. In our proposal idle stations are bypassed, therefore the relevant delay produced in the standard token ring is minimized. This improvement is particularly significant at light and medium loads, and makes the proposed LAN suitable for voice applications. An access protocol for integration of voice and data is also described which meets the delay constraints of voice traffic while guaranteeing a minimum bandwidth requirement for data traffic. The performance of the SBP-Net is evaluated via simulation tools. Results obtained show significant improvement of delay-throughput characteristics compared with those of the token ring.

Two combined voice and data transmission protocols implemented on a folded unidirectional bus LAN are proposed. The first is a round-robin service protocol, while the second is a reverse round-robin service protocol. Data transmissions on both protocols and voice transmissions on the first protocol are based on a mechanism according to which a station starts transmitting when it detects an end of carrier on the outbound channel, and it aborts its transmission when it detects a transmission from upstream. In the second protocol, voice is transmitted in the reverse round exploiting the periodicity of voice. According to this mechanism, each station computes its transmission time by relying on the preceding transmissions. Separation of the two traffic types is achieved by the requirement for sharing the channel alternately in voice and data rounds. The transmission of data packets and voice call packets for setting up calls is assigned to the data round, while the transmission of voice packets is assigned to the voice round. In these protocols, access delay for voice packets can be bounded to a desirable upper limit by not allowing the transmission of data. The performance of the proposed protocols under various traffic conditions was studied via simulation tools.

A local area network (LAN) that provides a reverse order service discipline from round to round is presented. The network, Folded Bus with Control channel Network (FBC-Net), consists of two buses: a folded unidirectional data bus, and an auxiliary bus that coordinates access to the data bus. The FBC-Net provides bounded delay, a feature that makes it particularly suitable for voice transmission. An access protocol for integrating voice and data traffic is also described. This protocol meets the delay constraint for voice transmission, while at the same time guaranteeing sufficient bandwidth for data traffic transmission. The performance of the FBC-Net under various traffic conditions is evaluated via simulation.

Two new protocols integrating voice and data on a multiaccess broadcast bus LAN with reverse round robin service are presented. The protocols are based on a collision free scheduling delay access mechanism. According to this mechanism, each station computes its transmission time relying on the activity of the bus. In the first protocol, we use this mechanism for both voice and data traffic. In the second protocol, the data traffic is based on the above mechanism, while, for the voice traffic, we additionally exploit the periodicity of voice. Separation of the two traffic types is achieved by the requirement for sharing the channel alternately in voice and data rounds. The transmission of data packets and voice call packets for setting up calls is assigned to the data round while the transmission of voice packets is assigned to the voice round. The proposed protocols were studied via simulation tools. They satisfy the delay constraint of voice traffic and, at the same time, guarantee a sufficient bandwidth for data traffic. Results obtained under various traffic conditions are given.

An implicit token-passing bus local area network (LAN) that provides a reverse round robin service to the stations is presented. The network, named G-Net, consists of a unidirectional bus folded to create a topology similar to the letter G. The G-Net provides bounded delay, a feature that makes it suitable for voice traffic. The performance of the G-Net, is evaluated via simulation.