System for, and method of, managing voice congestion in a network environment

• US 5,579,301 A
• Filed: 02/28/1994
• Issued: 11/26/1996
• Est. Priority Date: 02/28/1994
• Status: Expired due to Term

• Current Assignee: Constellation Technologies LLC (Rockstar Consortium Inc.)
• Original Assignee: Micom Communications Corp. (BCE Incorporated)
• Inventors: Sheppard, Thomas C., Ganson, Douglas
• Primary Examiner(s): Chin, Wellington
• Assistant Examiner(s): VU, HUY DUY
• Application Number:
  US08/203,792
• Time in Patent Office: 1,002 Days
• Field of Search: 370/60, 370/60.1, 370/61, 370/94.1, 370/84, 370/94.2, 370/13, 370/17, 370/58.1, 370/58.2, 370/58.3, 370/79, 370/118, 370/82, 348/401
• US Class Current: 370/229
• CPC Class Codes: H04J 3/1688 the demands of the users being taken into account after redundancy removal, e.g. by predictive coding, by variable sampling reducing bandwidth of signals in general H04B1/66; in PCM-systems H04B14/046; removal of redundancy in telegraph communication H03M7/30
• CPC Class Codes: H04L 12/5602 Bandwidth control in ATM Networks, e.g. leaky bucket
• CPC Class Codes: H04L 12/6418 Hybrid transport
• CPC Class Codes: H04L 2012/5636 Monitoring or policing, e.g. compliance with allocated rate, corrective actions
• CPC Class Codes: H04L 2012/5651 Priority, marking, classes
• CPC Class Codes: H04L 2012/6456 Channel and bandwidth allocation
• CPC Class Codes: H04L 2012/6481 Speech, voice
• CPC Class Codes: H04L 2012/6497 Feedback to the source

Abstract

A first voice channel transmits voice signals into a second voice channel through a plurality of network nodes and data links. Preferably the voice signals are in packets each having a plurality of bits containing voice information and each having at least one additional bit to indicate whether a congestion has been encountered at any of the nodes. Preferably the voice signals in each packet have a particular bandwidth and a particular compression. When a congestion of a packet is encountered at one of the nodes, the node produces at the additional bit in the packet an indication that congestion has occurred. The packet with this indication then passes through the nodes to the second channel. The second channel then produces and sends to the first channel signals acknowledging the reception of the packets and the encountering of congestion. The first channel then reduces the bandwidths of the signals in the packets transmitted to the second channel and increases the compression of the signals in the packets. When the second channel receives these packets without encountering any congestion for at least a particular period of time, it sends a congestion clear signal to the first channel. The first channel then increases the bandwidth of the voice signals in the packets to the particular value and decreases the compression of these signals to the particular value. The second channel decompresses the voice signals in the packets and restores the voice signals to their original values.

Claims

1. In a method of preventing congestion in the transmission of voice signals between first and second voice channels through a network including network nodes and data links between the network nodes and between the network nodes and the channels, the steps of:

providing the voice signals with a particular bandwidth at the first channel,

sending the voice signals with the particular bandwidth through the data links and the network nodes to the second channel,

detecting congestion of the voice signals at an individual one of the network nodes,

generating a congestion encountered signal at the individual one of the nodes for transmission through the data links and the nodes to the second channel,

transmitting a congestion encountered signal from the second channel to the first channel,

reducing below the particular bandwidth the voice signals provided at the first channel for transmission to the second channel,

providing a particular level of data compression for the voice signals sent with the particular bandwidth from the first channel to the second channel, and

increasing the data compression for the voice signals at the first channel when the bandwidth of the signals is reduced below the particular bandwidth at the first channel,

generating a congestion encountered state at the second channel when the congestion is encountered at one of the network nodes,

eliminating the congestion encountered state at the second channel when the first channel has sent the voice signals with the reduced bandwidth for a particular period of time without any congestion in any of the nodes, and

transmitting a signal from the second channel to the first channel to indicate the elimination of the congestion encountered state at the second channel when the second channel eliminates the congestion encountered state in the second channel.

2. In a method as set forth in claim 1, comprising the steps of:

providing the voice signals with the particular bandwidth and the particular level of data compression in the first channel when the first channel receives an indication from the second channel that the congestion encountered state has been eliminated at the second channel, and

thereafter transmitting the voice signals with the particular bandwidth and the particular level of data compression from the first channel to the second channel.

3. In a method of preventing congestion in the transmission of voice signals between first and second telephone channels through a network including network nodes and data links between the network nodes and between the network nodes and the channels, comprising the steps at the second channel of:

receiving a congested encountered signal from an individual one of the nodes between the first and second channels when packets of voice signals are transmitted from the first channel in a particular bandwidth and with a particular compression,

entering a remote congested state in the second channel after receiving a congestion encountered signal from the individual one of the

thereafter transmitting the congestion encountered signal to the first channel to provide for the reduction in the bandwidth from the particular value and the increase in the compression from the particular value in the voice signals transmitted from the first channel to the second channel,

receiving the packets of the voice signals transmitted from the first channel at the reduced bandwidth and the increased compression,

providing a congestion clear signal when the second channel receives, without any congestion continuously for a particular period of time, the packets of the voice signals transmitted by the first channel at the reduced bandwidth and the increased compression, and

thereafter transmitting the congestion clear signal to the first channel to obtain the transmission of the packets of voice signals from the first channel to the second channel at the particular bandwidth and with the particular compression.

4. In a method as set forth in claim 3, comprising the step at the second channel of:

receiving the packets of the voice signals at the particular bandwidth and with the particular compression after transmitting the congestion clear signal to the first channel.

5. In a method as set forth in claim 3, comprising the step at the second channel of:

clearing the remote congested state in the second channel after receiving without any congestion continuously for the particular period of time, the packets of the voice signals transmitted by the first signals at the reduced bandwidth and the increased compression and before transmitting the congestion clear signal.

6. In a method of preventing congestion in the transmission of voice signals between first and second telephone channels through a network including network nodes and data links between the network nodes and between the network nodes and the channels, the steps at the second channel of:

receiving a congested encountered signal from an individual one of the nodes between the first and second channels when voice signals are transmitted from the first channel in a particular bandwidth and with a particular compression,

transmitting the congestion encountered signal to the first channel to provide for the reduction in the bandwidth from the particular value and the increase in the compression from the particular value in the voice signals transmitted from the first channel to the second channel,

receiving the voice signals transmitted from the first channel at the reduced bandwidth and the increased compression,

providing a congestion clear signal when the second channel receives, without any congestion for a particular period of time, the voice signals transmitted by the first channel at the reduced bandwidth and the increased compression,

transmitting the congestion clear signal to the first channel to obtain the transmission of the voice signals from the first channel to the second channel at the particular bandwidth and with the particular compression,

entering a remote congested state in the second channel after receiving a congested encountered signal from the individual one of the nodes and before transmitting the congested encountered signal to the first channel, and

providing a congestion clear state when the second channel receives, without any congestion for a particular period of time, the voice signals transmitted by the first channel at the reduced bandwidth and the increased compression before it transmits the congestion clear signal to the first channel.

7. In a method of preventing congestion in the transmission of voice signals between first and second telephone channels through a network including network nodes and data links between the network nodes between the network nodes and the channels, comprising the steps of:

providing successive packets of voice signals each containing a plurality of bits representing voice information in compressed form and each containing at least one particular bit indicating whether or not congestion has been encountered,

detecting the encounter of congestion at an individual one of the different nodes between the first channel and the second channel,

indicating in the particular bit in the packet the encounter of congestion at one of the different nodes between the first channel and the second channel;

receiving the packets at the second channel with the particular bit indicating the encounter of congestion,

sending from the second channel to the first channel an acknowledgement of the sending of the successive packets of voice signals, the acknowledgement including an indication of the encounter of congestion in the transmission of the packets of voice signals between the first and second channels, and

thereafter sending the successive packets of voice signals at a reduced bandwidth and with an increased compression from the first channel to the second channel.

8. In a method as set forth in claim 7, comprising the steps of:

removing the indication of the encounter of congestion in the particular bit in the packets when the congestion at the nodes has been removed, and

thereafter sending from the second channel to the first channel the acknowledgement with the particular bit indicating that the congestion has been removed.

9. In a method as set forth in claim 7, comprising the steps of:

indicating at the second channel the encounter of congestion between the first and second channels when an encounter of congestion is detected at one of the nodes between the first and second channels, and

removing the indication at the second channel of the encounter of congestion between the first and second channels when there is no encounter of congestion at the nodes between the first and second channels for a particular period of time.

10. In a method as set forth in claim 9, comprising the steps of:

transmitting a congestion clear signal from the second channel to the first channel when the indication of the encounter of congestion is removed at the second channel, and

increasing the bandwidth of the voice signals at the first channel when the congestion clear signal is transmitted from the second channel to the first channel.

11. In a method of preventing congestion in the transmission of voice signals between first and second telephone channels through a network including network nodes and data links between the network nodes and between the network nodes and the telephone channels, the steps at the first channels of:

providing successive packets of voice signals each containing bits indicating the characteristics of the voice signals in the packets and each providing at least one additional bit to indicate the presence or absence of packet congestion at any one of the successive nodes between the first and second channels and each having a particular bandwidth,

receiving an acknowledgement from the second channel of the receipt at the second channel of the packets of voice signals, each acknowledgement containing an indication of the presence or absence of packet congestion at any one of the successive nodes between the first and second channels,

reducing below the particular bandwidth the bandwidth of the voice signals in the packets transmitted from the first channel to the second channel when the first channel receives an acknowledgement with an indication of the presence of packet congestion at one of the successive nodes between the first and second channels,

providing the voice signals in each packet with a particular compression when the voice signals have the particular bandwidth, and

providing the voice signals in each packet with an increased compression greater than the particular compression when the voice signals have a bandwidth less than the particular bandwidth.

12. In a method as set forth in claim 11, comprising the steps at the first channel of:

providing an indication of a congestion in one of the nodes between the first and second channels when the first channel receives a congestion encountered signal from the second channel, and

removing the indication in the channel of the congestion in one of the nodes when the second channel transmits to the first channel an indication that the congestion has been cleared.

16. In a method as set forth in claim 11, comprising the steps at the first channel of:

increasing the bandwidth to the particular bandwidth, and reducing the compression to the particular compression, when the first station receives an acknowledgement from the second station that the packet congestion has been eliminated at the second station.

13. In a method of preventing congestion in the transmission of voice signals between first and second telephone channels including network nodes and data links between the network nodes and between the network nodes and the telephone channels, comprising the steps at the second channel of:

receiving the voice signals in successive packets at a particular bandwidth and with a particular compression after the travel of these signals from the first channel through the network nodes and the data links to the second channel, each of the packets having a plurality of bits representing voice information and at least one particular bit representing the occurrence of congestion or lack of congestion of the packets of voice signals in the network nodes and the data links,

acknowledging to the first channel the reception of the packets of voice signals from the first channel at the particular bandwidth and with the particular compression and any indication in such packets of the congestion of the voice signals, and

thereafter receiving the packets of the voice signals from the first channel, at a reduced bandwidth relative to the particular bandwidth and an increased compression relative to the particular compression, of the voice signals in the packets when the second channel provides an indication to the first channel of a congestion in the voice signals in the network nodes and the data links.

14. In a method as set forth in claim 13, comprising the steps at the second channel of:

receiving the packets of voice signals at the reduced bandwidth relative to the particular bandwidth and at the reduced compression relative to the particular compression for a particular period of time without any indication in the packets of congestion, and

thereafter sending to the first channel an indication that the occurrence of congestion has been cleared.

15. In a combination as set forth in claim 14, comprising the steps at the second channel of:

producing a congestion encountered signal before the acknowledgement of such encounter of congestion to the first channel, and

removing the congestion encountered indication when the packets of voice signals have been received for the particular period of time without any indication of congestion.

17. In a method as set forth in claim 14, comprising the step at the second channel of:

thereafter receiving the packets of voice signals from the first channel at the particular bandwidth and with the particular compression after sending to the first channel the indication that the occurrence of congestion has been cleared.

18. In a method of preventing congestion in the transmission of voice signals between first and second voice channels through a network including network nodes and data links between the network nodes and between the network nodes and the channels, comprising the steps of:

providing the voice signals with a particular bandwidth and with a particular compression at the first channel,

sending the voice signals with the particular bandwidth and the particular compression from the first channel through the data links and the network nodes to the second channel,

detecting congestion of the voice signals at an individual one of the network nodes,

generating a congestion encountered signal at the individual one of the nodes for transmission through the data links and the nodes to the second channel,

transmitting a congestion encountered signal from the second channel to the first channel when the congestion encountered signal is received at the second channel, the congestion encountered signal indicating only the existence or lack of existence of a congestion, and

reducing below the particular bandwidth the voice signals provided at the first channel for transmission to the second channel and simultaneously increasing the compression of the voice signals at the first channel above the particular compression, and

thereafter transmitting a signal from the second channel to the first channel, after the transmission by the first channel of the signals at the reduced bandwidth and the increased compression for a particular period of time and the reception of such signals at the second channel, to indicate that the congestion encountered state at the second channel has been eliminated.

19. In a method of preventing congestion in the transmission of voice signals between first and second telephone channels through a network including network nodes and data links between the network nodes and between the network nodes and the telephone channels, comprising the steps at the first channel of:

providing at the first channel successive packets of voice signals each containing binary bits indicating the characteristics of the voice signals in the packets and each having a particular bandwidth and a particular compression,

receiving at the first channel an acknowledgement from the second channel of the receipt at the second channel of the packets of voice signals, each acknowledgement containing an indication in an additional binary bit of the presence or absence of packet congestion at any one of the successive nodes between the first and second channels,

reducing below the particular bandwidth at the first channel the bandwidth of the voice signals in the packets transmitted from the first channel to the second channel, and increasing the compression of the voice signals above the particular compression, when the first channel receives an acknowledgement from the second channel with an indication in the additional binary bit of the presence of packet congestion at one of the successive nodes between the first and second channels, and

increasing the bandwidth of the voice signals at the first channel to the particular bandwidth, and reducing the compression of the voice signals to the particular compression, when the first channel receives an acknowledgement from the second channel in the additional binary bit that the packet congestion has been eliminated at the second channel.

20. In a method of preventing congestion in the transmission of voice signals between first and second voice channels through a network including network nodes and data links between the network nodes and between the network nodes and between the channels, comprising the steps of:

providing the voice channels at the first channel with a particular bandwidth and a particular compression,

sending the voice signals from the first channel with the particular bandwidth and the particular compression through the data links and the network nodes to the second channel,

detecting congestion of the voice signals at an individual one of the network nodes,

generating a congestion encountered signal at the individual one of the network nodes for transmission through the data links and the network nodes to the second channel,

entering a remote congested state at the second channel when a congestion encountered signal is generated at the individual one of the network nodes,

sending a congestion encountered signal from the second channel to the first channel, the congestion encountered signal indicating only the entering or lack of entering of the remote congested state at the second station,

entering at the first channel the congested encountered signal transmitted from the second channel, and

reducing the bandwidth of the voice signals below the particular bandwidth and increasing the compression of the voice signals above the particular compression, in response to the local congested state entered at the first channel, in the voice signals sent from the first channel to the second channel.

21. In a method as set forth in claim 20, further comprising the step of:

sending the voice signals at the reduced bandwidth and the increased compression from the first channel to the second channel, and

clearing the remote congested state at the second channel when the second channel receives the voice signals from the first channel at the reduced bandwidth and the increased compression for a particular period of time without the generation at the second channel of any congestion encountered signal.

22. In a method as set forth in claim 21, additionally comprising the step of:

sending a congestion clear signal from the second channel to the first channel when the second channel clears the remote congested state in the second channel.

23. In a method as set forth in claim 22, additionally comprising the step of:

clearing the local congested signals from the first channel when the first channel receives the congestion clear signal from the second channel.

24. In a method as set forth in claim 22,

clearing the local congested state at the first channel when the first channel receives the congestion clear signal from the second channel, and

increasing to the particular bandwidth the bandwidth of the voice signals, and reducing to the particular compression the compression of the voice signals, sent from the first channel to the second channel when the local congested state is cleared at the first channel.

25. In a method of preventing congestion in the transmission of voice signals between first and second telephone channels including network nodes and data links between the network nodes and between the network nodes and the telephone channels, comprising the steps at the second channel of:

receiving the voice signals in successive packets at a particular bandwidth and a particular compression after the travel of these signals from the first channel through the network nodes and the data links to the second channel, each of the packets having a plurality of bits representing voice information and at least one particular bit representing the occurrence or lack of occurrence of congestion of the packets of voice signals in the network nodes and the data links,

entering a remote congested state in the second channel when congestion has been encountered in one of the network nodes and data links between the first and second channels,

returning a congestion encountered signal from the second channel to the first channel, the congestion encountered signal indicating only the entering or lack of entering of the remote congested state in the second station,

receiving the packets of the voice signals from the first channel, at a reduced bandwidth and an increased compression relative to the particular bandwidth and the particular compression, after the return of the congestion encountered signal from the second channel to the first channel, and

clearing the remote congested state in the second channel after the second channel has received the voice signals from the first channel at the reduced bandwidth and the increased compression for a particular period of time without any congestion.

26. In a method as set forth in claim 25, comprising the additional step at the second channel of:

returning a congestion clear signal to the first channel after clearing the remote congested state in the second channel.

27. In a method as set forth in claim 26, comprising the additional step at the second channel of:

receiving the packets of the voice signals from the first channel at the particular bandwidth and the particular compression after returning the compression clear signal to the second channel.