Method and system for sending return messages in mpls networks
AssigneeBritish Telecommunications public limited company
InventorPeter j Willis
Life of this patent
Estimating the term…
Abstract
A method for sending a message via a label switch telecommunications network, in particular an MPLS network. The method comprises identifying at a first router (20) an input label (B) attached to the message and using the first label (B) to identify a output label (C) that defines a forward path for the message. This is done by reading the label table (28) in the router (20). Once the output label (C) is identified, the input label (B) is replaced with the output label (C) and the message and the output label (C) together are sent to another node (22) of the network. When a return message (32) is to be sent, input labels for the forward message path are used as output labels for the return message path (34).
Claims25
A method for sending a message via a label switch telecommunications network, the method comprising:
- identifying at a first node a first label attached to the message;
- using the first label to identify a second label associated with the first label, the second label defining a forward path for the message;
- replacing the first label with the second label;
- sending the message and the second label to another node of the network;
- sending a return message from the said other node together with the second label to the first node;
- using the second label to identify the first label, the first label defining a return path for the message, and
- replacing the second label with the first label.
A method for sending a message via a label switch telecommunications network, the method comprising:
- identifying at a first node a first label attached to the message;
- using the first label to identify a second label associated with the first label, the second label defining a forward path for the message;
- replacing the first label with the second label;
- sending the message and the second label to another node of the network;
- receiving a return message from the said other node together with the second label at the first node;
- using the second label to identify the first label, the first label defining a return path for the message, and
- replacing the second label with the first label.
A return message that is a product of the method of any one of the preceding claims.
A computer program, preferably on a data carrier or a computer readable medium, the computer program being for processing messages at a node in a label switch telecommunications network, preferably an MPLS network, the computer program comprising instructions for:
- identifying a first label attached to a message;
- using the first label to identify a second label associated with the first label, the second label defining a forward path for the message;
- replacing the first label with the second label;
- sending the message and the second label to another node of the network;
- receiving a return message from the said other node together with the second label;
- using the second label to identify the first label, the first label defining a return path for the message, and
- replacing the second label with the first label.
A telecommunication node or router for sending a message in a label switch telecommunications network, the node or router comprising:
- means for identifying a first label attached to a message;
- means operable to use the first label to identify a second label associated with the first label, the second label defining a forward path for the message;
- means for replacing the first label with the second label;
- means for sending the message and the second label to another node of the network;
- means for receiving a return message from the said other node together with the second label;
- means operable to use the second label to identify the first label, the first label defining a return path for the message, and
- means for replacing the second label with the first label.
Dependencies are inferred from the claim text.