Transfer rate controlling device and method thereof

A transfer rate controlling device for controlling a transmission rate of a transmitting terminal when the transmitting terminal multicasts a fixed-length packet to a plurality of receiving terminals in a network where a transfer rate allowed by a path to a receiving terminal is notified to the transmitting terminal by a management fixed-length packet while the transmitting terminal transfers a fixed-length packet to the receiving terminal, comprising:

• extracting means for extracting transfer rate information from management fixed-length packets which are sent from the plurality of receiving terminals to the transmitting terminal;
• calculating means for obtaining a parameter instructing a transmission rate of the transmitting terminal by performing a predetermined calculation for a plurality of sets of transfer rate information extracted by said extracting means;
• and notifying means for notifying the transmitting terminal of the parameter obtained by said calculating means;
• a buffer for storing a fixed-length packet which is transmitted from the transmitting terminal, said fixed-length packet being copied for transferring said fixed-length packet to the plurality of receiving terminals in correspondence with paths to the plurality of receiving terminals;
• transmitting means for reading a fixed-length packet from said buffer according to the transfer rate extracted by said extracting means corresponding to a path on which the management fixed-length packet including the extracted transfer rate has been transferred, and for transmitting the read fixed-length packet via the path;
• monitoring means for monitoring the number of fixed-length packets stored in said buffer for each of the paths to the plurality of receiving terminals;
• and
• monitoring result notifying means for notifying said calculating means of a monitoring result of said monitoring means, wherein said calculating means changes a method for calculating the parameter base on notification from said monitoring result notifying means.

A transfer rate controlling device for controlling a transmission rate of a transmitting terminal in a network where a fixed-length packet is multicast from the transmitting terminal to a plurality of receiving terminals, comprising:

• detecting means for detecting transfer rates allowed by the plurality of receiving terminals or by paths to the plurality of receiving terminals;
• calculating means for obtaining an average value of the plurality of transfer rates detected by said detecting means as a parameter instructing the transmission rate of the transmitting terminal;
• and
• notifying means for notifying the transmitting terminal of the parameter obtained by said calculating means.

A transfer rate controlling device for controlling a transmission rate of a transmitting terminal when the transmitting terminal multicasts a fixed-length packet to a plurality of receiving terminals in a network where a transfer rate allowed by a path to a receiving terminal is notified to the transmitting terminal by a management fixed-length packet while the transmitting terminal transfers a fixed-length packet to the receiving terminal, comprising:

• extracting means for extracting the transfer rate from a management fixed-length packet which arrives at the transmitting terminal;
• calculating means for obtaining a parameter instructing a transmission rate by performing a predetermined calculation for a plurality of transfer rates extracted by said extracting means;
• and
• controlling means for controlling the transmission rate of the transmitting terminal based on the parameter obtained by said calculating means.

A transfer rate controlling method for controlling a transmission rate of a transmitting terminal when the transmitting terminal multicasts a fixed-length packet to a plurality of receiving terminals in a network where a transfer rate allowed by a path to a receiving terminal is notified to the transmitting terminal by a management fixed-length packet while the transmitting terminal transfers a fixed-length packet to the receiving terminal, comprising the steps of:

• extracting the transfer rate from a management fixed-length packet which proceeds to the transmitting terminal;
• obtaining a parameter instructing a transmission rate of the transmitting terminal by performing a predetermined calculation for a plurality of extracted transfer rates;
• and
• notifying the transmitting terminal of the obtained parameter.