METHOD AND APPARATUS FOR SENDING DELAY SENSITIVE INFORMATION ASSISTED BY PACKET SWITCHED NETWORKS

• US 20020016837A1
• Filed: 02/10/1998
• Published: 02/07/2002
• Est. Priority Date: 02/10/1998
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: 3Com Corporation (HP Inc.)
• Inventors: NAUDUS, STANLEY T.
• Granted Patent: US 6,412,006 B2
• Time in Patent Office: Days
• US Class Current: 709/224
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/121 by minimising delays
• CPC Class Codes: H04L 45/3065 for real time traffic

Abstract

A method and apparatus for sending delay sensitive information assisted by packet switched networks for network nodes in a computer network is presented. Delay sensitive information such as voice information is sent over higher cost delay sensitive connections. Control and status information for the delay sensitive connections is sent in control messages over lower cost packet switched connections to the nodes in the computer network. Information in the control messages is stored in status tables on the network nodes. The status table is used by network nodes to determine the status of any delay sensitive connections in the computer network and is used to establish a lowest cost connection path or a desired quality of service connection path when a delay sensitive connection between network nodes is requested. Sending delay sensitive control and status information over the lower cost packet switch connections to the network nodes and using status tables on the network nodes to establish delay sensitive connections significantly decreases the costs associated with using delay sensitive connections.

Claims

1. In a computer network with a plurality of network nodes, the network nodes having a packet switched connection to a packet switched network, and selected ones of the network nodes having a delay sensitive connection to selected other ones of the network nodes, wherein the delay sensitive connection includes a plurality of individual delay sensitive channels, a method for determining a status of a delay sensitive connection from any network node in the computer network, the method comprising the following steps:

receiving a selection input on a first network node to change a status of a delay sensitive connection between the first network node and a second network node;

changing the status of the delay sensitive connection based on the selection input; and

sending a control message with a predetermined protocol on the packet switched network from the first network node to the other network nodes in the computer network indicating the change in status of the delay sensitive connection.

2. A computer readable medium having stored therein instructions for causing a central processing unit in a network node to execute the method of claim 1.

3. The method of claim 1 wherein a third network node is connected to the first node with a delay sensitive connection, but is not connected to the second network node with a delay sensitive connection, further comprising:

determining from the third network node with the control message if a delay sensitive connection channel from the first network node to the second network node is available, and if so,

establishing an indirect delay sensitive connection from the third network node to the second network node using a delay sensitive connection channel from the delay sensitive connection between the third network node and the first network node, and the available delay sensitive channel between the first network node and the second network node.

4. The method of claim 1, further comprising:

storing information received in the control message in status tables on the network nodes;

dynamically updating the status tables upon receiving additional control messages; and

determining from a network node with a status table current status information for any delay sensitive connections in the computer network.

5. The method of claim 1 further comprising:

storing information received in control messages in status tables on the network nodes; and

determining from a network node with a status table a lowest cost delay sensitive connection path between the network node and any other network node in the computer network.

6. The method of claim 5 wherein the lowest cost delay sensitive connection path is a shortest delay sensitive connection path with a desired quality of service

7. The method of claim 1 wherein information contained in the control message includes any of:

network node routing information;

network node connection preference information;

network node connection cost information;

network node addresses;

network node dial numbers quality of service;

or network node Private Branch Exchange dial numbers for the delay sensitive connection.

8. The method of claim 1 wherein the step of changing the status of the delay sensitive connection includes any of:

establishing the delay sensitive connection;

releasing the delay sensitive connection;

or changing the characteristics of the delay sensitive connection.

9. The method of claim 1 wherein the step of changing the status of the delay sensitive connection includes changing a status for any of the plurality of delay sensitive connection channels in the delay sensitive connection.

10. The method of claim 1 wherein the packet switched network is the Internet.

11. In a computer network with a plurality of network nodes, the network nodes having a packet switched connection to a packet switched network, selected ones of the network nodes having a delay sensitive connection to selected other ones of the network nodes, wherein the delay sensitive connection includes a plurality of individual delay sensitive channels, a method for determining a lowest cost delay sensitive connection, the method comprising the following steps:

maintaining on the network nodes status tables containing information from control messages sent over the packet switched connection to the network nodes indicating changes in status of delay sensitive connections in the computer network;

receiving a selection input on a first network node to create a delay sensitive connection to a second network node;

determining from the first network node with a status table a lowest cost connection path to create the delay sensitive connection; and

establishing the delay sensitive connection between the first network node and the second network node with the determined lowest cost delay sensitive connection path.

12. A computer readable medium having stored therein instructions for causing a central processing unit on a network node to execute the method of claim 11.

13. The method of claim 11 wherein the step of determining with the status table a lowest cost connection path to create the delay sensitive connection includes any of a determining the shortest delay sensitive connection path, or a delay sensitive connection path with a desired quality of service.

14. The method of claim 11 further comprising:

determining with the status table if all delay sensitive connection channels on the delay sensitive connection from the first network node to the second network node are idle, and if so,

determining with a predictive release function when the delay sensitive connection can be released between the first network node and second network node.

15. The method of claim 14 wherein the predictive release function includes using statistical information collected for time of establishment, duration and time of release of delay sensitive connections in the computer network.

16. The method of claim 11 further comprising:

determining with the status table if all delay sensitive connection channels on the delay sensitive connection from the first network node to the second network node are idle, and if so,

setting a timer with a predetermined timer value, wherein the predetermined timer value is based on the delay sensitive connection type; and

removing the delay sensitive connection between the first network and the second network node when the timer expires.

17. The method of claim 11 wherein the step of determining with the status table a lowest cost connection path includes first checking selected ones of network nodes for available delay sensitive connection channels in the status table based on predetermined connection preferences before checking for available delay sensitive connection channels on other network nodes.

19. The apparatus of claim 18 further comprising:

control message receiver, for receiving control messages from the packet switched connection;

status table, for storing the control messages in a status table in a memory of the apparatus; and

status table updater, for dynamically updating the status table as control messages are received on the packet switched connection; and

lowest cost connection determiner, for determining a lowest cost delay sensitive connection path between two nodes in the computer network using the status table.

20. The apparatus of claim 18 further comprising:

delay sensitive connection releaser, for releasing a delay sensitive connection with a predictive release function.

18. A computer network communication apparatus, the apparatus comprising:

status receiver, for receiving a selection input on a first network node to change a status of a delay sensitive connection between a first network node and a second network node in a computer network;

status changer, for changing the status of the delay sensitive connection based on the selection input; and

control message sender, for sending a control message with a predetermined protocol on a packet switched network from the first network node to other network nodes in a computer network indicating the change in status of the delay sensitive connection.