Network switching system with asynchronous and isochronous interface

• US 8,615,007 B2
• Filed: 07/19/2012
• Issued: 12/24/2013
• Est. Priority Date: 04/07/1999
• Status: Expired due to Term

• Current Assignee: Juniper Networks Incorporated
• Original Assignee: Juniper Networks Incorporated
• Inventors: Koyama, Akira
• Primary Examiner(s): MARCELO, MELVIN C
• Application Number:
  US13/553,563
• Publication Number:
  US 20120281692A1
• Time in Patent Office: 523 Days
• Field of Search: 370/356, 370/401
• US Class Current: 370/356
• CPC Class Codes: H04L 12/40097 Interconnection with other networks LAN interconnection over a bridge based backbone H04L12/462; single bridge functionality H04L12/462
• CPC Class Codes: H04L 12/4013 Management of data rate on the bus systems modifying transmission characteristics according to link quality H04L1/0001
• CPC Class Codes: H04L 12/403 with centralised control, e.g. polling
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways
• CPC Class Codes: H04M 7/121 Details of network access arrangements or protocols

Abstract

To provide a switching system with telephone switching function mainly on the basis of hardware processing by using isochronous channel which is a real time communication channel. The switching system comprises a gateway node connected with ISDN (Integrated Services Digital Network) and PSTN (Public Switched Telephone Network), and one or more extension nodes, and a serial bus such as IEEE 1394 bus. The gateway node transforms data rate of outside line into data rate of extension node, and the other way around, and secure a seamless communication channel. Concretely, the gateway node secures an isochronous channel, according to a request from the extension nodes or the outside line, and executes switching such as transfer or reservation. A resource manager holds a table for managing the gateway node and extension node.

Claims

1. A device comprising:

one or more processors to;

receive a request to establish a connection for transmitting voice signals between a first extension node and a second extension node, at least one of the first extension node or the second extension node being connected to the device via a serial bus,

secure, based on the request, a bidirectional isochronous channel, and

transmit information identifying the bidirectional isochronous channel to one of the first extension node or the second extension node to enable the connection to be established.

2. The device of claim 1, where the one or more processors are further to:

determine that the connection is associated with a telephone number of the first extension node,

convert the telephone number to an identifier associated with the first extension node, and

notify, via the serial bus, each of a plurality of other extension nodes connected to the serial bus, of the established connection between the first extension node and the second extension node using the identifier.

3. The device of claim 1, where the one or more processors are further to:

determine an occurrence of a reset of the serial bus,

determine a change to an identifier associated with the at least one of the first extension node or the second extension node that is caused by the occurrence of the reset of the serial bus,

transmit, via the serial bus and to the at least one of the first extension node or the second extension node, information identifying the change to the identifier to prevent a transmission of the voice signals from being interrupted.

4. The device of claim 3, where the occurrence of the bus reset is caused by a connection of a third extension node to the serial bus.

5. The device of claim 1, where the one or more processors are further to:

determine a change to an identifier associated with the at least one of the first extension node or the second extension node,

transmit, via the serial bus and to the at least one of the first extension node or the second extension node, information identifying the change to the identifier to prevent a transmission of the voice signals from being interrupted.

6. The device of claim 1, where the first extension node and the second extension node are connected to the serial bus, and

where the one or more processors are further to:

determine a state of the first extension node based on receiving the request,

update control information based on the determined state, and

transmit, prior to the connection being established, information identifying the updated control information to the first extension node and the second extension node.

7. The device of claim 1, where the one or more processors are further to:

determine a termination of the connection, and

release the bidirectional isochronous channel based on the termination of the connection.

8. A method comprising:

receiving, by a network device, a request to establish a connection for transmitting voice signals between a first extension node and a second extension node, the first extension node being connected to the network device via a serial bus;

securing, by the network device, a bidirectional isochronous channel based on the request; and

transmitting, by the network device, information identifying the bidirectional isochronous channel to the first extension node to enable the connection to be established.

9. The method of claim 8, further comprising:

determining that the connection is associated with a telephone number of the first extension node;

converting the telephone number to an identifier associated with the first extension node; and

notifying, via the serial bus, each of a plurality of extension nodes connected to the serial bus, of the established connection between the first extension node and the second extension node using the identifier,

the plurality of extension nodes including the first extension node and the second extension node.

10. The method of claim 8, further comprising:

determining an occurrence of a reset of the serial bus;

determining a change to an identifier associated with the first extension node,

the change to the identifier being caused by the occurrence of the reset of the serial bus;

transmitting, via the serial bus and to the first extension node, information identifying the change to the identifier to prevent an interruption of a transmission of the voice signals.

11. The method of claim 10, where the occurrence of the bus reset is caused by a connection of a third extension node to the serial bus.

12. The method of claim 8, further comprising:

determining a change to an identifier associated with the first extension node, and

transmitting, via the serial bus and to the first extension node, information identifying the change to the identifier to prevent a transmission of the voice signals from being interrupted.

13. The method of claim 8, where the first extension node and the second extension node are connected to the serial bus, the method further comprising

determining a state of the first extension node based on receiving the request;

and

transmitting, prior to the connection being established, information identifying the state of the first extension node to the first extension node and the second extension node.

14. The method of claim 8, further comprising:

determining a termination of the connection; and

releasing the bidirectional isochronous channel based on the termination of the connection.

15. A method comprising:

determining, by a first device, a first device identifier for a second device and a second device identifier, that is different from the first device identifier, for a third device, the first device, the second device, and the third device being connected via a bidirectional serial bus;

determining, by the first device, a first bus identifier for the second device and a second bus identifier, that is different from the first bus identifier, for the third device;

establishing, by the first device and using the bidirectional serial bus, a communication session between the second device and the third device;

determining, by the first device and during the communication session, an occurrence of a bus reset of the bidirectional serial bus;

determining, by the first device and during the communication session, a change of at least one of the first device identifier or the second device identifier resulting from the occurrence of the bus reset; and

notifying, by the first device and during the communication session, the second device and the third device of the change of the at least one of the first device identifier or the second device identifier to minimize an intermission of communication caused by the occurrence of the bus reset.

16. The method of claim 15, where establishing the communication session includes:

securing, based on a request to establish the communication session, a first isochronous channel and a second isochronous channel; and

establishing the communication session over the first isochronous channel and the second isochronous channel.

17. The method of claim 15, where establishing the communication session includes:

receiving a request to establish the communication session from the second device,

transmitting, based on the request, a signal to the third device via an asynchronous channel, and

establishing the communication session via a pair of isochronous channels based on receiving, from the third device, a response to the signal.

18. The method of claim 15, where the occurrence of the bus reset results from a fourth device being connected to the bidirectional serial bus during the communication session.

19. The method of claim 18, where notifying the second device and the third device of the change of the at least one of the first device identifier or the second device identifier includes:

transmitting, to the second device and the third device, information identifying a third device identifier and a third bus identifier, the third device identifier and the third bus identifier being associated with the fourth device.

20. The method of claim 15, further comprising:

determining a termination of the communication session; and

releasing the first isochronous channel and the second isochronous channel based on the termination of the communication session.