Patent ID: 6959323

Claim:
A method for multicasting data messages to members of a multicast group, the multicast group comprising a sequencer, one or more clients, one or more data servers, and one or more commit servers, the method comprising the steps of: transmitting a first data message to the members of the multicast group; each data server that receives the first data message requesting the sequencer to assign a first sequence number to the first data message, the first sequence number being from a sequence of numbers allocated to the data messages, said first sequence number following all sequence numbers assigned prior to assignment of the first sequence number; assigning the first sequence number to the first data message, in response to the sequencer receiving a first quantity of the requests to assign a first sequence number to the first data message said first quantity of requests being other than a majority of requests from the data servers; notifying the commit servers of the assignment of the first sequence number to the first data message; each of the commit servers sending to the sequencer an acknowledgment of the notification of the assignment of the first sequence number to the first data message, in response to being notified of the assignment of the first sequence number to the first data message; committing the first sequence number to the first data message, in response to the sequencer receiving a second quantity of the acknowledgments of the notification of the assignment of the first sequence number to the first data message; and informing the members of the multicast group of the commitment of the first sequence number to the first data message.