Abstract: An arbitration mechanism provides quality of service guarantees for time-sensitive signals sharing a local area computer network with non-time-sensitive traffic. Device adapters are placed at all access points to an Ethernet network. The device adapters limit admission rates and control the timing of all packets entering the network. By doing so, collisions are eliminated for time-sensitive traffic, thereby guaranteeing timely delivery. A common time reference is established for the device adapters. The time reference includes a frame with a plurality of phases. Each of the phases is assigned to a device adapter. Each device adapter is allowed to transmit packets of data onto the network only during the phase assigned thereto. The length of the phases may be modified in accordance with the number of packets to be transmitted by a particular device adapter. A master device adapter may be appointed to synchronize each of the device adapters.

Abstract: An arbitration mechanism provides quality of service guarantees for time-sensitive signals sharing a local area computer network with non-time-sensitive traffic. Device adapters are placed at all access points to an Ethernet network. The device adapters limit admission rates and control the timing of all packets entering the network. By doing so, collisions are eliminated for time-sensitive traffic, thereby guaranteeing timely delivery. A common time reference is established for the device adapters. The time reference includes a frame with a plurality of phases. Each of the phases is assigned to a device adapter. Each device adapter is allowed to transmit packets of data onto the network only during the phase assigned thereto. The length of the phases may be modified in accordance with the number of packets to be transmitted by a particular device adapter. One of the device adapters may be designated as a master timing device to synchronize each of the other device adapters.

Abstract: A network system for providing efficient transmission of real-time data and non-real-time data between a plurality of network devices, including an arbitration mechanism that provides a low cost and high performance mechanism for delivery of quality of service guarantees for time-sensitive data sharing a local area with non-time-sensitive data. Device adapters are placed at all access points to a local network. The device adapters limit admission rates and control the timing of all packets entering the network. An X-Hub placed at the center of the network provides for transparent, concurrent transport of signals transmitted by device adapters. Collisions may therefore be eliminated for time-sensitive traffic, thereby guaranteeing timely delivery. A common time reference is established for the device adapters and the X-Hub. The time reference defines a frame with a plurality of phases. Each of the phases defines a state of the X-Hub, and a state for each of the device adapters.