Virtual circuit configuration method

1. A method for configuring a virtual circuit set up between a first and a second terminal installation through which a data stream is intended to be transmitted, the virtual circuit being carried by an underlying path comprising a first link set up between the first terminal installation and an intermediate installation, a second link set up between the intermediate installation and the second terminal installation, and a third link set up between the intermediate installation and a third terminal installation, wherein the method comprises:

a step of receiving a configuration message by the third terminal installation, said message comprising at least the following parameters: an identifying parameter for the virtual circuit,

an identifying parameter for the underlying path carrying the virtual circuit, and a label determined by the first terminal installation, identifying the data stream;

a step of configuring a switching table of the third terminal installation by using said parameters, and

a step of processing the data stream by using the configured switching table, when the virtual circuit is switched from the second link to the third link following the detection of a fault on the second link.

2. The method as claimed in claim 1 , in which the configuration message also comprises a request to set up another virtual circuit, termed a backup virtual circuit, between the first and the third terminal installations, the backup virtual circuit being configured to transmit the data stream.

3. A terminal installation intended to form an end of a virtual circuit set up between a first and a second terminal installation through which a data stream is intended to be transmitted, the virtual circuit being carried by an underlying path comprising a first link set up between the first terminal installation and an intermediate installation, a second link set up between the intermediate installation and the second terminal installation, and a third link set up between the intermediate installation and the terminal installation,

wherein the terminal installation comprises:

means for receiving a configuration message comprising at least the following parameters: an identifying parameter for the virtual circuit, an identifying parameter for the underlying path carrying the virtual circuit, and a label determined by the first terminal installation, identifying the data stream;

means for configuring a switching table of the terminal installation by using said parameters; and

means for processing the data stream by using the configured switching table, when the virtual circuit is switched from the second link to the third link following the detection of a fault on the second link.

4. A non-transitory storage medium comprising a computer program stored thereon, wherein the computer program comprises program code instructions for implementation of a method for configuring a virtual circuit set up between a first and a second terminal installation through which a data stream is intended to be transmitted, when the program is executed by a processor, wherein the virtual circuit is carried by an underlying path comprising a first link set up between the first terminal installation and an intermediate installation, a second link set up between the intermediate installation and the second terminal installation, and a third link set up between the intermediate installation and a third terminal installation, and wherein the method comprises:

a step of receiving a configuration message by the third terminal installation, said message comprising at least the following parameters: an identifying parameter for the virtual circuit, an identifying parameter for the underlying path carrying the virtual circuit, and a label determined by the first terminal installation, identifying the data stream;

a step of configuring a switching table of the third terminal installation by using said parameters; and

a step of processing the data stream by using the configured switching table, when the virtual circuit is switched from the second link to the third link following the detection of a fault on the second link.

5. A method comprising:

generating a signal by a first terminal installation, the signal carrying a configuration message for a virtual circuit intended to be received by a terminal installation able to form an end of a virtual circuit set up between the first and a second terminal installation through which a data stream is intended to be transmitted, the virtual circuit being carried by an underlying path comprising a first link set up between the first terminal installation and an intermediate installation, a second link set up between the intermediate installation and the second terminal installation, and a third link set up between the intermediate installation and the terminal installation wherein the signal comprises at least the following parameters: an identifying parameter for the virtual circuit, an identifying parameter for the underlying path carrying the virtual circuit, and a label determined by the first terminal installation, identifying the data stream;

sending the signal carrying the configuration message to the terminal installation, said terminal installation comprising means for configuring a switching table by using said parameters, and

processing the data stream by using the configured switching table, when the virtual circuit is switched from the second link to the third link following the detection of a fault on the second link.

6. The method as claimed in claim 5 , wherein the signal furthermore comprises a request to set up another virtual circuit between the first terminal installation and the said terminal installation.

7. The method of claim 1 , wherein the virtual circuit is a pseudowire.

8. The terminal installation of claim 3 , wherein the virtual circuit is a pseudowire.

9. The non-transitory storage medium of claim 4 , wherein the virtual circuit is a pseudowire.

10. The method of claim 5 , wherein the virtual circuit is a pseudowire.