Abstract: In a communication network in which a group of connections has an assigned group bandwidth and each connection in the group has a minimum bandwidth, bandwidth usage is controlled by calculating the total current bandwidth allowed to the group, subtracting the total current bandwidth from the assigned group bandwidth, and adding the difference to each connection's current bandwidth allowance to calculate an explicit rate, according to which the connection's bandwidth allowance is controlled. The explicit rate is altered to a minimum explicit rate when, for example, the total bandwidth exceeds the group bandwidth. The minimum explicit rate of each connection is preferably calculated on the basis of the sum of the minimum bandwidths of the active connections in the group. These measures improve the fairness of bandwidth usage control.

Abstract: A cell transmitting device receives cells for transmission to a cell receiving device on a connection in a communication network. The connection has a minimum cell rate, established when the connection is set up. The cell transmitting device measures the input rate of cells to be transmitted on the connection, determines an allowable cell rate on the basis of the input rate and cell rate information supplied by the cell receiving apparatus, and transmits cells within the allowable cell rate. Under certain conditions, such as absence of cell traffic on the connection, the allowable cell rate is set to a lowest cell rate lower than the minimum cell rate, thereby enabling other connections to obtain higher cell rates.

Abstract: In a communication network in which a group of connections has an assigned group bandwidth and each connection in the group has a minimum bandwidth, bandwidth usage is controlled by calculating the total current bandwidth allowed to the group, subtracting the total current bandwidth from the assigned group bandwidth, and adding the difference to each connection's current bandwidth allowance to calculate an explicit rate, according to which the connection's bandwidth allowance is controlled. The explicit rate is altered to a minimum explicit rate when, for example, the total bandwidth exceeds the group bandwidth. The minimum explicit rate of each connection is preferably calculated on the basis of the sum of the minimum bandwidths of the active connections in the group. These measures improve the fairness of bandwidth usage control.

Abstract: A cell transmitting device receives cells for transmission to a cell receiving device on a connection in a communication network. The connection has a minimum cell rate, established when the connection is set up. The cell transmitting device measures the input rate of cells to be transmitted on the connection, determines an allowable cell rate on the basis of the input rate and cell rate information supplied by the cell receiving apparatus, and transmits cells within the allowable cell rate. Under certain conditions, such as absence of cell traffic on the connection, the allowable cell rate is set to a lowest cell rate lower than the minimum cell rate, thereby enabling other connections to obtain higher cell rates.

Abstract: Methoxyanthraquinones are produced from the corresponding nitroanthraquinones by reacting a nitroanthraquinone with methanol and an alkali in a reaction medium chiefly comprising methanol at a temperature of 50.degree.-130.degree. C under atmospheric or superatmospheric pressure in the presence of molecular oxygen wherein the dissolved oxygen concentration of the reaction medium is maintained at a value of at least 1 ppm.