Method of managing traffic flows in a wideband integrated services digital network, and a network for implementing the method

• US 5,130,978 A
• Filed: 11/23/1990
• Issued: 07/14/1992
• Est. Priority Date: 11/27/1989
• Status: Expired due to Term

• Current Assignee: Alcatel-Lucent France, SA (Nokia Corporation)
• Original Assignee: Alcatel-Lucent France, SA (Nokia Corporation)
• Inventors: Mobasser, Bahman
• Primary Examiner(s): Safourek, Benedict V.
• Assistant Examiner(s): SAMUEL, TEMESGHEN
• Application Number:
  US07/617,227
• Time in Patent Office: 599 Days
• Field of Search: 370/44.1, 370/85.12, 370/62, 370/110.1, 370/60, 370/58.1
• US Class Current: 370/231
• CPC Class Codes: H04L 12/5602 Bandwidth control in ATM Networks, e.g. leaky bucket
• CPC Class Codes: H04L 2012/5616 Terminal equipment, e.g. codecs, synch.
• CPC Class Codes: H04L 2012/563 Signalling, e.g. protocols, reference model
• CPC Class Codes: H04L 2012/5635 Backpressure, e.g. for ABR
• CPC Class Codes: H04L 2012/5636 Monitoring or policing, e.g. compliance with allocated rate, corrective actions
• CPC Class Codes: H04L 2012/5647 Cell loss
• CPC Class Codes: H04L 2012/5649 Cell delay or jitter

Abstract

Method and apparatus for controlling traffic flow in a wideband integrated services digital network including an asynchronous time division multiplexed switch network and a plurality of terminals operating at various data rates and providing different types of service. Control of traffic flow in the network is achieved by delaying data cells or allowing them to be lost, within limits that are predetermined as a function of the type of service provided by the terminals.

Claims

1. A method of managing traffic flows in a wideband integrated services digital network comprising an asynchronous time division multiplexed switching network and a plurality of terminals operating at various data rates and providing different types of service, the terminals transmitting and receiving data in the form of cells of fixed length and using a communications protocol adapted to asynchronous time division multiplexing;

wherein, in each terminal, said method comprises;

transmitting an acknowledgement whenever a particular terminal receives a cell;

continuing to transmit cells after having transmitted a first cell and while waiting to receive an acknowledgement corresponding to the first cell, and limiting the number of cells transmitted while waiting to a predetermined number;

then suspending cell transmission during a predetermined duration if the acknowledgement is not received before all of the predetermined number of the cells have been transmitted;

then retransmitting the first cell if the corresponding acknowledgement is not received during the predetermined duration;

and then releasing the connection occupied by said particular terminal if the acknowledgement is not received after a predetermined delay measured from the first transmission of the first cell;

wherein the predetermined values for the predetermined number, the predeterimined duration and the predetermined delay are functions of the type of service provided by said particular terminal;

and wherein, in the switching network, if close to congestion, said method comprises;

determining, for each connection, the values of the predetermined number, the predetermined duration and the predetermined delay as a function of the type of service being provided by the terminate connected to said each connection;

delaying a sequence of cells transmitted on said each connection, while limiting the number of cells in said sequence to a number which is less than or equal to the predetermined number; and

loosing a cell and other identical cells transmitted on said each connection, while limiting the duration corresponding to cell loss to a value less than the predetermined delay.

2. A wideband integrated services digital network comprising an asynchronous time division multiplexed switching network and a plurality of terminals operating at various data rates and providing different types of service, wherein each terminal is coupled to first means for receiving and transmitting data in the form of cells of fixed length in accordance with a communications protocol adapted to asynchronous time division multiplexing, and to second means controlling the first means, said second means comprises:

means for transmitting an acknowledgement whenever a particular terminal receives a cell;

means for continuing to transmit data cells after having tansmitted a first cell and while waiting to receive an acknowledgement corresponding to the first cell, and limiting the number of cells transmitted while waiting to a predetermined number which is a function of the type of service provided by said particular terminal;

means for then suspending cell transmission during a predetermined duration if the acknowledgement is not received before all of the predetermined number of the cells have been transmitted, the predetermined duration being a function of the type of service provided by said particular terminal;

means for then retransmitting the first cell if the corresponding acknowledgement is not received during the predetermined duration;

means for then releasing the connection occupied by said particular terminal if the acknowledgement is not received after a predetermined delay measured from the first transmission of the first cell, the predetermined delay being a function of the type of service provided by said particular terminal; and

wherein the switching network includes management means, said management means comprising;

means for determining the values of the predetermined number, the predetermined duration and the predetermined delay on each connection as a function of the type of service provided by the terminals interconnected by said each connection;

means for, if the network is very heavily loaded, delaying a sequence of cells transmitted over said each connection while limiting the number of cells in the sequence to the predetermined number and while limiting the delay to the predetermined delay; and

means for, if the network is close to congestion, loosing a cell and other identical cells retransmitted as a consequence by the terminal which transmitted the cell, while limiting the duration corresponding to cell loss to a value less than the predetermined delay.