Transmission device and label allocation method

A label allocation method in a network, which has a main route and a protection route that protects the main route, and which executes route control based on a label switching, comprising:

• reflecting, performed by a transmission device positioned at a branch between the main route and the protection route, including reflecting a label limit information included in a connection establishment request message for the main route into a label limit information included in a connection establishment request message for the protection route, when allocation of a related label, that is a label that relates the main route and the protection route, is necessary;
• waiting, performed by the transmission device, including waiting for a connection establishment response message for the protection route, after receiving a connection establishment response message for the main route corresponding to the connection establishment request message;
• acquiring, performed by the transmission device, including acquiring label limit information allocated to the protection route, from the connection establishment response message for the protection route;
• and
• allocating, performed by the transmission device, including allocating a label related to the label limit information acquired, to the main route.

A label allocation method in a network, which has a main route and a protection route that protects the main route, and which executes route control based on a label switching, comprising:

• waiting, performed by a transmission device positioned at a merge between the main route and the protection route, including waiting for a connection establishment request message for the protection route, after receiving a connection establishment request message for the main route, when allocation of a related label, that is a label that relates the main route and the protection route, is necessary;
• reflecting, performed by the transmission device, including reflecting a label limit information included in the connection establishment request message for the protection route into a label limit information included in the connection establishment request message for the main route;
• acquiring, performed by the transmission device after waiting for the connection establishment response message for the main route, including acquiring a label limit information allocated to the main route from a connection establishment response message for the main route;
• and
• allocating, performed by the transmission device, including allocating a label related to the label limit information acquired, to the protection route.