Patent ID: 8218549

Claim:
A method for communication, comprising: arranging a group of servers to receive multiple streams of multicast messages from message sources outside the group of servers and to deliver the multiple streams of multicast messages to recipients; receiving a new message stream from a source at the group of the servers including at least a first server in the group; upon receiving the new message stream at the first server, transmitting first protocol messages from the first server to the other servers in the group in order to verify that the other servers have received the new message stream; upon verifying that the other servers have received the new message stream by receiving replies from the other servers to the first protocol messages, sending a second protocol message from the first server to the other servers, instructing the other servers to begin processing the new message stream; and responsively to the second protocol message, adding the new message stream to the multiple streams delivered to the recipients from the servers and causing the servers to deliver all the multicast messages from all the message streams to all the recipients in the same order.