Arrangement for regulating traffic in a high speed data network

• US 5,231,631 A
• Filed: 03/16/1992
• Issued: 07/27/1993
• Est. Priority Date: 08/15/1989
• Status: Expired due to Term

• Current Assignee: AT&T, Inc.
• Original Assignee: AT&T, Inc.
• Inventors: Punj, Vikram, DeBruler, Dennis L., Buhrke, Rolfe E.
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): HOM, SHICK C
• Application Number:
  US07/853,353
• Time in Patent Office: 498 Days
• Field of Search: 370/94.2
• US Class Current: 370/230
• CPC Class Codes: H04L 12/5602 Bandwidth control in ATM Networks, e.g. leaky bucket
• CPC Class Codes: H04L 2012/5615 Network termination, e.g. NT1, NT2, PBX
• CPC Class Codes: H04L 2012/5629 Admission control
• CPC Class Codes: H04L 2012/563 Signalling, e.g. protocols, reference model
• CPC Class Codes: H04L 2012/5632 Bandwidth allocation
• CPC Class Codes: H04Q 11/0478 Provisions for broadband connections

Abstract

The invention relates to methods and apparatus for regulating traffic in a Broadband Integrated Services Digital Network (B-ISDN). Terminal adapters interface between terminals and the B-ISDN. Whenever a first terminal wishes to transmit a data message to a second terminal, the source adapter, connected to the first terminal, allocates transmit bandwidth for the transmission of the message and sends a request message to a destination adapter, connected to the second terminal, for checking availability of and allocating receive bandwidth. The data message is sent only if bandwidth has been allocated on both ends. Overflow traffic is throttled at the adapters before it enters the network, thereby reducing the number of data cells lost because of the limited storage of the network.

Claims

1. In a data network comprising one or more intermediate nodes, a method of allocating resources for transmission of data from a transmitting terminal connected to a transmitting ingress facility of said network to a receiving terminal connected to a receiving egress facility of said network, comprising the steps of:

determining, in said ingress facility, whether an amount of packet switching bandwidth required for the transmission of the data from the transmitting terminal to the receiving terminal is available at the transmitting terminal ingress facility to said network;

if said amount of packet switching bandwidth is available at the ingress facility, allocating said amount of bandwidth to the transmitting terminal;

if said amount of packet switching bandwidth is available at the ingress facility, transmitting a request message, to allocate said amount of bandwidth, from said ingress to said egress facility;

responsive to said request message, determining, in said egress facility, whether said amount of packet switching bandwidth is available at the receiving terminal egress facility from said network;

if said amount of packet switching bandwidth is available at the egress facility, allocating said amount of bandwidth in said egress facility to the receiving terminal; and

if said allocating steps have been executed successfully, transmitting data at the packet switching bandwidth allocated in said allocating steps from said ingress facility over ones of said intermediate nodes to said egress facility without checking for available packet bandwidth in intermediate nodes prior to commencement of said transmitting.

7. The method of claim 1 wherein the step of determining whether said amount of bandwidth is available at the egress comprises:

sending a request message from an ingress controller for said transmitting terminal to an egress controller for said receiving terminal;

responsive to receipt of the request message, checking for available receive bandwidth at the egress facility; and

sending a message from the egress controller to the ingress controller reporting on the result of the checking step.

8. The method of claim 7 further comprising:

if said checking step determines that said amount of bandwidth is available, allocating said amount of bandwidth.

10. The method of claim 1 wherein an ingress/egress controller for said transmitting terminal and an ingress/egress controller for said receiving terminal each comprise a terminal adapter for receiving data from and transmitting data to a plurality of connected terminals.

11. The method of claim 1 wherein said data network is a broadband ISDN network.

2. In a data network comprising one or more intermediate nodes, a method of allocating resources for transmission of data from a transmitting terminal connected to a transmitting ingress facility of said network to a receiving terminal connected to a receiving egress facility of said network, comprising the steps of:

determining, in said ingress facility, whether an amount of bandwidth required for the transmission of the data from the transmitting terminal to the receiving terminal is available at the transmitting terminal ingress facility to said network;

if said amount of bandwidth is available at the ingress facility, allocating said amount of bandwidth to the transmitting terminal;

if said amount of bandwidth is available at the ingress facility, transmitting a request message, to allocate said amount of bandwidth, from said ingress to said egress facility;

responsive to said request message, determining, in said egress facility, whether said amount of bandwidth is available at the receiving terminal egress facility from said network; and

if said amount of bandwidth is available at the egress facility, allocating said amount of bandwidth in said egress facility to the receiving terminal;

if said amount of bandwidth is not available at the ingress facility, or is not available at the egress facility, recording a request for the amount of bandwidth at an ingress controller for the transmitting terminal;

if said allocating steps have been executed successfully, transmitting data at the packet switching bandwidth allocated in said allocating steps from said ingress facility over ones of said intermediate nodes to said egress facility without checking for available packet bandwidth in intermediate nodes prior to commencement of said transmitting.

3. In a data network, a method of allocating resources for transmission of data from a transmitting terminal connected to a transmitting ingress facility of said network to a receiving terminal connected to a receiving egress facility of said network, comprising the steps of:

determining, in said ingress facility, whether an amount of bandwidth required for the transmission of the data from the transmitting terminal to the receiving terminal is available at the transmitting terminal ingress facility to said network;

if said amount of bandwidth is available at the ingress facility, allocating said amount of bandwidth to the transmitting terminal;

if said amount of bandwidth is available at the ingress facility, transmitting a request message, to allocate said amount of bandwidth, from said ingress to said egress facility;

responsive to said request message, determining, in said egress facility, whether said amount of bandwidth is available at the receiving terminal egress facility from said network; and

if said amount of bandwidth is available at the egress facility, allocating said amount of bandwidth in said egress facility to the receiving terminal;

if said amount of bandwidth is not available at the ingress facility, or is not available at the egress facility, recording a request for the amount of bandwidth at an ingress controller for the transmitting terminal;

recording, in said ingress controller, data defining the destination, the amount of bandwidth, and data identifying a time of the request.

4. The method of claim 3 further comprising the step of:

periodically checking for requests for bandwidth in the recorded data and repeating attempts to allocate said requested bandwidth in an ingress controller for said receiving terminal and an egress controller for said transmitting terminal.

5. The method of claim 4 further comprising the steps of:

separately recording all requests whose age exceeds a predetermined threshold; and

attempting to allocate bandwidth to the separately recorded requests on a priority basis.

6. The method of claim 5 wherein said step of attempting to allocate comprises:

9. In a data network, a method of allocating resources for transmission of data from a transmitting terminal connected to a transmitting ingress facility of said network to a receiving terminal connected to a receiving egress facility of said network, comprising the steps of:

determining, in said ingress facility, whether an amount of bandwidth required for the transmission of the data from the transmitting terminal to the receiving terminal is available at the transmitting terminal ingress facility to said network;

if said amount of bandwidth is available at the ingress facility, allocating said amount of bandwidth to the transmitting terminal;

if said amount of bandwidth is available at the ingress facility, transmitting a request message, to allocate said amount of bandwidth, from said ingress to said egress facility;

responsive to said request message, determining, in said egress facility, whether said amount of bandwidth is available at the receiving terminal egress facility from said network; and

if said amount of bandwidth is available at the egress facility, allocating said amount of bandwidth in said egress facility to the receiving terminal;

wherein the step of determining whether said amount of bandwidth is available at the egress comprises;

sending a request message from an ingress controller for said transmitting terminal to an egress controller for said receiving terminal;

responsive to receipt of the request message, checking for available receive bandwidth at the egress facility; and

sending a message from the egress controller to the ingress controller reporting on the result of the checking step;

wherein the checking step further comprises;

if all of said amount of bandwidth is not available at the egress facility, but at least a predetermined fraction of said amount of bandwidth is available at the egress facility, allocate the at least a predetermined fraction; and

the sending step comprises;

sending a response message to the ingress controller reporting how much bandwidth was allocated.

12. In a data network, a method of allocating resources for transmission of data from a transmitting terminal connected to a transmitting ingress facility of said network to a receiving terminal connected to a receiving egress facility of said network, comprising the steps of:

determining, in said ingress facility, whether an amount of bandwidth required for the transmission of the data from the transmitting terminal to the receiving terminal is available at the transmitting terminal ingress facility to said network;

if said amount of bandwidth is available at the ingress facility, allocating said amount of bandwidth to the transmitting terminal;

if said amount of bandwidth is available at the ingress facility, transmitting a request message, to allocate said amount of bandwidth, from said ingress to said egress facility;

responsive to said request message, determining, in said egress facility, whether said amount of bandwidth is available at the receiving terminal egress facility from said network; and

if said amount of bandwidth is available at the egress facility, allocating said amount of bandwidth in said egress facility to the receiving terminal;

if said amount of bandwidth is not available at the ingress facility, or is not available at the egress facility, recording a request for the amount of bandwidth at an ingress controller for the transmitting terminal;

recording, in said ingress controller, data defining the destination, the amount of bandwidth, and data identifying a time of the request;

wherein the step of allocating bandwidth at an ingress controller for said transmitting terminal comprises;

periodically sorting by age, requests for which transmit bandwidth has not been allocated; and

attempting to allocate bandwidth for oldest requests first.

13. A terminal adapter, for connection to a data network comprising one or more intermediate nodes, comprising:

a terminal interface for communicating between the adapter and a plurality of terminals;

a network interface for communicating between the adapter and a data network;

storage means for storing data messages receivable via the terminal interface from the terminals for transmission via the network interface over the network;

storage means for data messages receivable via the network interface from the network for transmission via the terminal interface to the terminals; and

processor means operative under the control of a program for controlling the following operations;

determining whether an amount of bandwidth for transmitting a data message from a transmitting terminal to a receiving terminal via the terminal adapter is recorded as available;

if said amount of bandwidth is available, allocating said amount of bandwidth to the transmitting terminal;

sending a message via the network interface over the network to a destination terminal adapter connected to a destination terminal of the message requesting allocation of said amount of bandwidth; and

responsive to receipt of a message from the destination terminal adapter confirming allocation of the amount of bandwidth for the reception of the data message, sending the data message from the storage means for messages receivable from the terminals via the network interface to the network over ones of said intermediate nodes selected by said network without checking for available packet bandwidth in intermediate nodes prior to commencement of said sending.

14. The terminal adapter of claim 13 wherein the terminal interface comprises:

protocol handler means for interfacing between the two storage means and the data from and to the terminals.

15. The terminal adapter of claim 13 wherein the processor means comprises:

storage means for storing requests to transmit messages and for storing data defining blocks of bandwidth allocated to transmit and receive messages over the network.

16. A method of allocating resources in a broadband ISDN network for transmission of data from a transmitting terminal connected to a transmitting ingress facility of said network to a receiving terminal connected to a receiving egress facility of said network, comprising the steps of:

determining an amount of bandwidth required for the transmitting terminal;

determining, in said ingress facility, whether the amount of bandwidth is available at a source terminal adapter, the source adapter connected to the network and the transmitting terminal;

if the amount of bandwidth is available at the source adapter, allocating the amount of bandwidth to the transmitting terminal;

if the amount of bandwidth is available at the source adapter, transmitting a request message, to allocate said amount of bandwidth, from said ingress to said egress facility;

responsive to said request message, determining, in said egress facility, whether the amount of bandwidth is available at a destination terminal adapter, the destination adapter connected to the network and the receiving terminal;

if the amount of bandwidth is available at the destination adapter, allocating the amount of bandwidth in said egress facility to the receiving terminal;

if the amount of bandwidth is not available at the source adapter, or is not available at the destination adapter, recording in the source adapter, data defining the destination, the amount of bandwidth, and data identifying a time of a request for the amount of bandwidth;

periodically checking for requests for bandwidth in the recorded data and repeating attempts to allocate said requested bandwidth in the source adapter and the destination adapter;

separately recording all requests whose age exceeds a predetermined threshold; and

attempting to allocate bandwidth to the separately recorded requests on a priority basis by transmitting repeated request messages to allocate bandwidth at the destination adapter;

wherein the step of determining whether bandwidth is available at the destination adapter comprises;

sending a request message from the source adapter to the destination adapter;

responsive to receipt of the request message, checking for available receive bandwidth at the destination adapter; and

sending a message from the destination adapter to the source adapter reporting on the result of the checking step;

wherein the checking step comprises;

if the amount of bandwidth is not available at the destination adapter, but at least a predetermined fraction of the amount of bandwidth is available at the destination adapter, allocate the at least a predetermined fraction; and

the sending step comprises;

sending a response message to the source adapter reporting how much bandwidth was allocated;

wherein the step of allocating at the source adapter comprises;

periodically sorting by age, requests for which transmit bandwidth has not been allocated; and

attempting to allocate bandwidth for oldest requests first.

17. In a data network comprising one or more intermediate nodes, a method of allocating resources for transmission of data from a transmitting terminal connected to a transmitting ingress facility of said network to a receiving terminal connected to a receiving egress facility of said network, comprising:

determining, in said ingress facility, if adequate packet switching bandwidth for transmission of the data is available at said ingress facility having allocable packet switching bandwidth on a common transmission medium to the network, the ingress facility connected to the transmitting terminal, and determining, in said egress facility if adequate packet switching bandwidth for reception of the data is available at said egress facility having allocable packet switching bandwidth on a common transmission medium from the network, the egress facility connected to the receiving terminal; and

when said adequate packet switching bandwidth is available at both the ingress facility and the egress facility, allocating said adequate packet switching bandwidth to said transmission of data over ones of said intermediate nodes selected by said network without checking for available packet bandwidth in intermediate nodes prior to commencement of said transmission of data.

18. The method of claim 17 further comprising:

transmitting said data after said adequate packet switching bandwidth is allocated.

19. A terminal adapter, for connection to a data network comprising one or more intermediate nodes, comprising:

means, responsive to a request to transmit a data message, for allocating transmit bandwidth;

means responsive to said request for transmitting a signaling message requesting allocation of receive packet switching bandwidth in another terminal adapter; and

means responsive to receipt of a signaling message from said another terminal adapter confirming allocation of receive packet switching bandwidth for initiating transmission of said data message over ones of said intermediate nodes selected by said network without checking for available packet bandwidth in intermediate nodes prior to said initiating transmission.

21. The terminal adapter of claim 19 wherein said means responsive to receipt of a signaling message is further responsive, to receipt of a signaling message denying allocation of receive bandwidth, for recording a request for allocating said transmit bandwidth.

20. A terminal adapter, for connection to a data network comprising one or more intermediate nodes, comprising:

means, responsive to receipt of a signaling message from another terminal adapter, for testing for availability of receive packet switching bandwidth;

means, responsive to said means for testing, for allocating said receive bandwidth if available and for transmitting a reply message for enabling or disabling transmission of a data message from said another terminal adapter over ones of said intermediate nodes selected by said network without checking for available packet bandwidth in intermediate nodes prior to said enabling.