Patent application number | Description | Published |
20100238788 | Connection verification for MPLS label switched paths and pseudowires - In one embodiment, a connection verification (CV) message is initiated from an initiating maintenance end point (MEP) for an MPLS LSP, the CV message carried in a packet having a time-to-live (TTL) value of 1. Each maintenance intermediate point (MIP) along the MPLS LSP receives the packet and decrements the TTL, and in response to determining that the TTL equals 0, examines a payload of the packet to determine that the packet carries the CV message. The MIP may then append its MIP ID to a route record field of the payload having any previous MIP IDs of upstream MIPs, and forwards the CV message downstream along the MPLS LSP in a packet having a TTL value of 1. The end MEP receives the CV message, and sends a CV reply having the route record field with MIP IDs and an end MEP ID to the initiating MEP. | 09-23-2010 |
20100238795 | Restoring multi-segment pseudowires following failure of a switching PE device - In one embodiment, a protected switching provider edge (S-PE) and a backup S-PE may be operated, where the protected S-PE has at least one multi-segment pseudowire (MS-PW) and is between a first and second provider edge (PE) on the MS-PW. To protect the protected S-PE, the first and second PE may be informed of the backup S-PE and a backup label to reach the second and first PE, respectively, via the backup S-PE to remain on the MS-PW. Upon detecting loss of connectivity with the protected S-PE, the first and/or second PE may forward packets of the MS-PW to the backup S-PE with the corresponding backup label to reach the second or first PE, respectively, on the MS-PW. | 09-23-2010 |
20100238812 | Operating MPLS label switched paths and MPLS pseudowire in loopback mode - In one embodiment, an initiating maintenance end point (MEP) may transmit a lock message to lock a circuit traversing one or more maintenance intermediate points (MIPs) between the initiating MEP and an end MEP. The initiating MEP may then transmit an in-band packet containing a loopback request to a particular MIP along the circuit using a particular time-to-live (TTL) value in the packet to reach the particular MIP. Upon receiving the packet at the particular MIP, and in response to determining that the TTL has expired, the particular MIP inspects the packet to discover the loopback request, and correspondingly operates in a loopback mode. | 09-23-2010 |
20110280121 | SYSTEM AND METHOD FOR SUMMARIZING ALARM INDICATIONS IN A NETWORK ENVIRONMENT - An example method includes detecting a failure at a first network element, the failure is associated with a link between the first network element and a second network element. The method also includes generating a list of network elements to be notified based on the failure, the second network element is included on the list. The method further includes generating an alarm indication signal (AIS) message, the AIS message identifies a plurality of tunnels affected by the failure. The AIS message is communicated to the second network element. In more detailed embodiments, each link between the first network element and the second network element includes a globally unique link identifier, which includes an associated autonomous system number. The globally unique link identifier can represent a string to be associated with the plurality of tunnels, the globally unique link identifier includes a source address and a destination address. | 11-17-2011 |
20120198064 | USING CONTEXT LABELS TO SCALE MAC TABLES ON COMPUTER NETWORK EDGE DEVICES - In one embodiment, an access component of a local network edge device receives traffic, and generates a frame for the traffic that includes a remote context label that identifies an access component of the remote network edge device to which the traffic is to be forwarded upon arrival at the remote network edge device, and a virtual circuit label corresponding to a particular virtual service of the traffic. The local network edge device forwards the frame towards the remote network edge device. In another embodiment, the frame may be received at a core component of the remote network edge device, an in response to the remote context label identifying an access component of the remote network edge device, forwarded to the access component, which determines the particular virtual service, and forwards the traffic from the frame out the access component towards an endpoint for the traffic. | 08-02-2012 |
20130148489 | CONNECTION VERIFICATION FOR MPLS LABEL SWITCHED PATHS AND PSEUDOWIRES - In one embodiment, a maintenance intermediate point (MIP) receives a packet traveling along a multi-protocol label switching (MPLS) label switched path (LSP) that extends from a first maintenance end point (MEP) to a second MEP. The receiving MIP decrements a time-to-live (TTL) value in a header of the packet. In response the TTL value in the header of the packet equaling a particular value, the receiving MIP examines an associated channel header (ACH) field in an operations, administration, and maintenance (OAM) message stored in a payload of the packet, and determines a particular OAM function to perform based on a code in the ACH field. The receiving MIP performs the particular OAM function. | 06-13-2013 |
20130155877 | OPERATING MPLS LABEL SWITCHED PATHS AND MPLS PSEUDOWIRE IN LOOPBACK MODE - In one embodiment, a circuit that extends between a head-end label switching router (LSR) and a tail-end LSR and traverses one or more intermediate LSRs is locked to data plane traffic. The head-end LSR transmits a packet along the circuit that includes a particular time-to-live (TTL) value configured to expire at a particular intermediate LSR at which loopback is to occur. The circuit is used in a loopback mode. The head-end LSR transmits along the circuit a packet that includes a cease loopback request. The circuit ceases to be used in the loopback mode. The circuit is unlocked to permit the circuit to pass data plane traffic. | 06-20-2013 |
20140010072 | SIGNALING CO-ROUTED AND NON CO-ROUTED LSPS OF A BIDIRECTIONAL PACKET TE TUNNEL - Particular embodiments may enable setup and signaling of co-routed and non co-routed label switched paths (LSPs) of a bidirectional packet traffic engineering (TE) tunnel in an unambiguous manner with respect to provisioning of the LSPs/tunnel. A head-end node may set up the bidirectional packet TE tunnel by computing a forward (and possibly a reverse) direction LSP, and then signal the bidirectional TE tunnel utilizing, e.g., extensions to an associated Resource Reservation Protocol (RSVP) signaling method. The extensions to the associated RSVP signaling method include a plurality of additional Association Types of an Extended Association object carried in a RSVP Path message transmitted by the head-end node to the tail-end node over the forward direction LSP, wherein the additional Association Types explicitly identify the provisioning of the forward and reverse direction LSPs as co-routed or non co-routed. | 01-09-2014 |
20140112124 | Protection of a Bidirectional Label Switched Path - In one embodiment, a primary bidirectional LSP is established between an originating LSP packet switching device and a destination LSP packet switching device through an intermediate packet switching device. A corresponding backup LSP is also established. The originating LSP packet switching device sends a particular label switched packet to the destination LSP packet switching device over the primary bidirectional LSP. An intermediate packet switching device sends the particular label switched packet back to the originating LSP packet switching device over the primary bidirectional LSP in response to an error condition identified as affecting the primary bidirectional LSP towards the destination LSP packet switching device. The originating LSP packet switching device receives the particular label switched packet and sends it to the destination packet switching device over the backup LSP. | 04-24-2014 |
20140143409 | Bandwidth On-Demand Services in Multiple Layer Networks - Bandwidth usage for an existing communication tunnel between a first device and second device is monitored. A determination is made that additional bandwidth is required for communication between the first network device and the second network device. A determination is made that for the addition of the additional bandwidth would exceed available bandwidth for the existing tunnel. Additional bandwidth is established between the first network device and the second network device. | 05-22-2014 |
20140211629 | SYSTEM AND METHOD FOR REPORTING OUT-OF-RESOURCES (OOR) CONDITIONS IN A DATA NETWORK - A system and method for advertising out-of-resources (OOR) conditions for entities, such as nodes, line cards and data links, in a manner that does not involve using a maximum cost to indicate the entity is “out-of-resources.” According to the technique, an OOR condition for an entity is advertised in one or more type-length-value (TLV) objects contained in an advertisement message. The advertisement message is flooded to nodes on a data network to inform them of the entity's OOR condition. Head-end nodes that process the advertisement message may use information contained in the TLV object to determine a path for a new label switched path (LSP) that does not include the entity associated with the OOR condition. | 07-31-2014 |
20140286341 | SIGNALING CO-ROUTED AND NON CO-ROUTED LSPS OF A BIDIRECTIONAL PACKET TE TUNNEL - Particular embodiments may enable setup and signaling of co-routed and non co-routed label switched paths (LSPs) of a bidirectional packet traffic engineering (TE) tunnel in an unambiguous manner with respect to provisioning of the LSPs/tunnel. A head-end node may set up the bidirectional packet TE tunnel by computing a forward (and possibly a reverse) direction LSP, and then signal the bidirectional TE tunnel utilizing, e.g., extensions to an associated Resource Reservation Protocol (RSVP) signaling method. The extensions to the associated RSVP signaling method include a plurality of additional Association Types of an Extended Association object carried in a RSVP Path message transmitted by the head-end node to the tail-end node over the forward direction LSP, wherein the additional Association Types explicitly identify the provisioning of the forward and reverse direction LSPs as co-routed or non co-routed. | 09-25-2014 |