This set of rules implements the most basic behaviour of the protocol that can be usedwhen IP multicast is available. This mode can be useful in local area networks where thistransmission mode usually works properly.
IP multicast address: The splitter uses an IP multicast address (and a port)where all peers of the team wait for receiving chunks. Notice that the peersonly receive chunks (never send them to the multicast channel because thesplitter does all the work).
Peer arrival: An incoming peer must contact with the splitter in order to jointhe team. After that, the splitter sends to the peer the stream header overthe TCP using a temporal unicast connection.
Buffering in peers: Packets in transit can suffer different transmission delays due to thejitter∗∗Variations in the network latency.,even producing that they arrive out of order. For this reason, the splitterenumerates every chunk of stream with a 16-bit counter, producing a packet withthe format:
IMS_packet = [chunk_number, chunk]
Peers store the received IMS_packets in a buffer whose sizecan be different in each peer depending on the maximun tolerated delay.
Relation between the buffer sizeand chunk numberupper bound :Due to practical reasons, the upper bound for the chunk number should be a powerof two. In order to minimize the probability of receiving two or more chunks withthe same number (remember that chunks can be reordered in transit),must be amultiple of ,i.e.: