MULTI-DESTINATION BURST PROTOCOL

摘要

Multicast transmissions are efficient but do not allow for individual acknowledgement that the data was received by each receiver. This is not acceptable for isochronous systems that require specific levels of QoS for each device. A multimedia communications protocol is provided that uses a novel multi-destination burst transmission protocol in multimedia isochronous systems. The transmitter establishes a bi-directional burst mode for multicasting data to multiple devices and receiving Reverse Start of Frame (RSOF) delimiters from each multicast-destination receiver in response to multiple SOF delimiters, thus providing protocol-efficient multi-destination acknowledgements.

主权项

1. A method for multicast communications in a carrier sense multiple access (CSMA) network including a transmitter and a multicast group of receiving devices including at least two receiving devices, the method comprising:
making a multicast transmission to the multicast group using a Start of Frame (SOF) delimiter that includes a frame length of a first bidirectional burst pseudo contention free period during which the transmitter communicates without contention; wherein the SOF further includes an identification of a first one of the receiving devices in the multicast group that is allowed to transmit in a first pseudo contention free period; responding by said first one of said receiving devices to the first SOF delimiter with a first acknowledgement of status of received multicast MPDU data; transmitting a second SOF before an end of the frame length of the first SOF that is addressed to a second one of the receiving devices; acknowledging by the second one of the receiving devices the status of the received multicast MPDU data using a second acknowledgement; and continuing subsequent SOF/acknowledgement process until one of: a last one of the receiving devices in the multicast group has been addressed by a SOF and has responded or the first bidirectional burst is terminated.