Dynamic configuration of cross-domain pseudowires

A first border router positioned between a first domain and a second domain of a computer network and in communication with a second border router of the second domain, the first border router comprising:

• at least one interface that receives a label distribution protocol (LDP) message from a first provider edge device in accordance with a label distribution protocol (LDP), wherein the first provider edge device is located at an edge of the first domain of the computer network, and wherein the LDP message includes data for configuring a cross-domain pseudowire (PW) as a multi-segment pseudowire (MS-PW);
• a control unit that includes:
• an LDP module that parses the received LDP message to extract the data for configuring the cross-domain PW;
• a translation module that transforms the extracted data to conform to a format defined by a routing protocol different from the LDP that includes extensions for advertising the cross-domain PW configuration data;
• and
• a routing protocol module that forms a routing protocol message that includes the transformed data,
• wherein the at least one interface outputs the routing protocol message to the second intermediate device to establish the cross-domain PW from the first provider edge device to a second provider edge device located at an edge of the second domain of the computer network to span the first domain and the second domain,
• wherein the at least one interface receives an encapsulated layer 2 (L2) data unit from the second border router, wherein the encapsulated L2 data unit comprises a header specifying a label stack containing a first label reserved by the first border router for use by a first segment of the MS-PW and a L2 data unit, and
• wherein the first segment of the MS-PW comprises a first pseudowire (PW) between the first and second border routers;
• wherein the LDP module removes the label from the label stack of the header of the encapsulated L2 data unit, pushes a second label reserved by the first provider edge device for use by a second segment of the MS-PW onto the label stack of the header of the encapsulated L2 data unit, wherein the second segment of the MS-PW comprises a second PW between the first provider edge device and the first border router, and
• wherein, after pushing the second label onto the label stack, the at least one interface forwards the encapsulated L2 data unit to the first provider edge device for delivery to a customer network.

A network system comprising:

• a first customer network that includes a first customer edge device positioned at the edge of the first customer network;
• a second customer network that includes a second customer edge device positioned at the edge of the second customer network;
• a first domain that includes:
• a first network device positioned at a border of the first domain;
• and
• a first provider edge device positioned at an edge of the first domain that is communicatively coupled to the first network device and the first customer edge device;
• and
• a second domain that includes:
• a second network device positioned at a border of the second domain that is communicatively coupled to the first network device;
• and
• a second provider edge device positioned at an edge of the second domain that is communicatively coupled to the second network device and the second customer edge device,
• wherein the first network device includes:
• at least one interface that receives a label distribution protocol (LDP) message from the first provider edge device in accordance with a label distribution protocol (LDP),
• wherein the LDP message includes a forwarding equivalence class-128 (FEC-128) element that stores data for configuring a cross-domain pseudowire (PW) including a group identifier field that stores group identifier data defining a group identifier, a pseudowire (PW) identifier field that stores PW identifier data defining a PW identifier and a provider edge (PE) device address field that stores PE address data defining a PE address assigned to the first provider edge device,
• wherein the first provider edge device only supports a forwarding equivalence class-128 (FEC-128) element of LDP to define the data for configuring the cross-domain PW, and
• wherein the second provider edge device only supports a FEC-129 element of LDP to define the data for configuring the cross-domain PW;
• a control unit that includes:
• an LDP module that parses the received LDP message to extract the group identifier data, the PW identifier data and the PE address data from the FEC-128 element of the LDP message;
• a translation module that transforms the group identifier data, the PW identifier data and the PE address data to conform to one or more extensible fields for advertising the cross-domain PW configuration data of a routing protocol different from the LDP;
• and
• a routing protocol module that forms a routing protocol message to include the one or more extensible fields to contain the group identifier data, the PW identifier data and the PE address data extracted from the LDP message,
• wherein the at least one interface outputs the routing protocol message to the second network device to establish the cross-domain PW from the first provider edge device to the second provider edge device located at an edge of the second domain of the computer network to span the first domain and the second domain;
• and
• wherein the second network device includes:
• at least one interface that receives the routing protocol message;
• and
• a control unit that includes:
• a routing protocol module that parses the received routing protocol message to extract the group identifier data, the PW identifier data and the PE address data stored to the one or more extensible fields;
• a translation module that transforms the extracted group identifier data, the extracted PW identifier data and the extracted PE address data to generate transformed data that conforms to the FEC-129 element;
• and
• an LDP module that generates an LDP message having a FEC-129 element that stores the transformed data,
• wherein the at least one interface of the second network device outputs the LDP message having the FEC-129 element to the second provider edge device.

A non-transitory computer-readable storage medium comprising instructions for causing a processor to:

• receive, with a first border router, a label distribution protocol (LDP) message from a first provider edge device in accordance with a label distribution protocol, the first border router is positioned between a first domain and a second domain of a computer network and in communication with a second intermediate device of the second domain, wherein the first provider edge device is located at an edge of the first domain of the computer network, and wherein the LDP message includes data for configuring a cross-domain pseudowire (PW) as a multi-segment pseudowire (MS-PW);
• parse, with the first border router, the received LDP message to extract the data for configuring the cross-domain PW;
• transform, with the first border router, the extracted data to conform to a format defined by a routing protocol that includes extensions for advertising the cross-domain PW configuration data, wherein the routing protocol is different than the LDP;
• form, with the first border router, a routing protocol message that includes the transformed data;
• and
• output, with the first border router, the routing protocol message to the second border router to establish the cross-domain PW from the first provider edge device to a second provider edge device located at an edge of the second domain of the computer network to span the first domain and the second domain;
• receive an encapsulated layer 2 (L2) data unit from the second border router, wherein the encapsulated L2 data unit comprises a header specifying a label stack containing a first label reserved by the first border router for use by a first segment of the MS-PW and a L2 data unit, and wherein the first segment of the MS-PW comprises a first pseudowire (PW) between the first and second border routers;
• remove the label from the label stack of the header of the encapsulated L2 data unit;
• push a second label reserved by the first provider edge device for use by a second segment of the MS-PW onto the label stack of the header of the encapsulated L2 data unit, wherein the second segment of the MS-PW comprises a second PW between the first provider edge device and the first border router;
• and
• after pushing the second label onto the label stack, forward the encapsulated L2 data unit to the first provider edge device for delivery to a customer network.

A method comprising:

• receiving, with a first-route reflector, a label distribution protocol (LDP) message from a first provider edge device in accordance with the label distribution protocol (LDP), the first route reflector is positioned between a first domain and a second domain of a computer network and in communication with a second route reflector of the second domain, wherein the first provider edge device is located at an edge of the first domain of the computer network, and wherein the LDP message includes data for configuring a cross-domain pseudowire (PW) as a single-segment pseudowire (SS-PW);
• parsing, with the first route reflector, the received LDP message to extract the data for configuring the cross-domain PW, the data including a label assigned to the SS-PW by the first provider edge device;
• transforming, with the first route reflector, the extracted data to conform to a format defined by a routing protocol different from the LDP that includes extensions for advertising the cross-domain PW configuration data;
• forming, with the first route reflector, a routing protocol message to include the transformed data so as to signal the label reserved for use by the SS-PW;
• and
• outputting, with the first route reflector, the routing protocol message to the second intermediate device to establish the cross-domain PW from the first provider edge device to a second provider edge device located at an edge of the second domain of the computer network to span the first domain and the second domain;
• wherein the second route reflector is positioned between the first route reflector and the second provider edge device,
• wherein the first route reflector is positioned between the first provider edge device and the second route reflector.

A first route reflector positioned between a first domain and a second domain of a computer network and in communication with a second route reflector of the second domain, the first route reflector comprising:

• at least one interface that receives a label distribution protocol (LDP) message from a first provider edge device in accordance with a label distribution protocol (LDP), wherein the first provider edge device is located at an edge of the first domain of the computer network, and wherein the LDP message includes data for configuring a cross-domain pseudowire (PW) as a single-segment pseudowire (SS-PW);
• a control unit that includes:
• an LDP module that parses the received LDP message to extract the data for configuring the cross-domain PW, the data including a label assigned to the SS-PW by the first provider edge device;
• a translation module that transforms the extracted data to conform to a format defined by a routing protocol different from the LDP that includes extensions for advertising the cross-domain PW configuration data;
• and
• a routing protocol module that forms a routing protocol message that includes the transformed data so as to signal the label reserved for use by the SS-PW, wherein the at least one interface outputs the routing protocol message to the second intermediate device to establish the cross-domain PW from the first provider edge device to a second provider edge device located at an edge of the second domain of the computer network to span the first domain and the second domain;
• wherein the second route reflector is positioned between the first route reflector and the second provider edge device,
• wherein the first route reflector is positioned between the first provider edge device and the second route reflector.

A non-transitory computer-readable storage medium comprising instructions for causing a processor of a first route reflector to:

• receive a label distribution protocol (LDP) message from a first provider edge device in accordance with the label distribution protocol (LDP), the first route reflector is positioned between a first domain and a second domain of a computer network and in communication with a second route reflector of the second domain, wherein the first provider edge device is located at an edge of the first domain of the computer network, and wherein the LDP message includes data for configuring a cross-domain pseudowire (PW) as a single-segment pseudowire (SS-PW);
• parse the received LDP message to extract the data for configuring the cross-domain PW, the data including a label assigned to the SS-PW by the first provider edge device;
• transform the extracted data to conform to a format defined by a routing protocol different from the LDP that includes extensions for advertising the cross-domain PW configuration data;
• form a routing protocol message to include the transformed data so as to signal the label reserved for use by the SS-PW;
• and
• output the routing protocol message to the second intermediate device to establish the cross-domain PW from the first provider edge device to a second provider edge device located at an edge of the second domain of the computer network to span the first domain and the second domain;
• wherein the second route reflector is positioned between the first route reflector and the second provider edge device,
• wherein the first route reflector is positioned between the first provider edge device and the second route reflector.