59 results about "Label switching router" patented technology

Detecting if a label-switched path (LSP) is functioning properly. To test that packets that belong to a particular Forwarding Equivalence Class (FEC) actually end their MPLS LSP on an label switching router (LSR) that is an egress for that FEC, a request message carrying information about the FEC whose LSP is being verified may be used. The request message may be forwarded like any other packet belonging to that FEC. A basic connectivity test as well as a fault isolation test are supported. In a basic connectivity test mode, the packet should reach the end of the LSP, at which point it is sent to the control plane of the egress LSR. The LSR then verifies that it is indeed an egress for the FEC. In a fault isolation test mode, the packet is sent to the control plane of each transit LSR, which performs various checks that it is indeed a transit LSR for the LSP. The transit LSR may also return further information that helps check the control plane against the data plane, i.e., that forwarding matches what the routing protocols determined as the path. A reliable return path is used for the reply.

Path determination constraints may be encoded in the form of a program having one or more instructions. Each of instructions may include an operation code, and operands (or pointers to locations where operands are stored). In this way, an extensible, interoperable way for a nodes (e.g., label-switching routers) to communicate constraints within a network is provided. Such constraints may be inserted (e.g., as one or more CONSTRAINT objects) into signaling messages (e.g., a PATH RSVP message). By enabling the signaling of constraints, the determination of constraint-based (label-switched) paths can be distributed among a number of (label-switching) routers or other nodes. Upon receiving a message with constraints (e.g., a CONSTRAINT object(s)), a node may (i) ignore the constraints if the node is a tail-end node (label-switching router), (ii) apply the constraints to a link if the next hop in the (label-switched) path is strict, and/or (iii) perform a constraint-based path determination to a next hop if the next hop is loose.

The invention relates to quick heavy-route method and label switching router. The method comprises: setting standby path for label switching path based on constrained routing and binding with the label switching path, first node of label switching path receiving notice information with path protection type-length-value TLV from insert knot of standby path when the label switching path is in failure, switching data of failure path to standby path for label transmission. The inventive example provides a label exchange tunnel based on constrained condition as prefabricated standby path to protect CR-LSP and avoid link and node failure.

A distributed LSR sends data from a first edge LSR, across a non-MPLS network, to a second edge LSR, thereby enabling a non-MPLS network to interface transparently with MPLS networks. This enables a VPN to use a public network to communicate from one portion of the network to another, remote portion. The distributed LSR includes an ingress gateway logically positioned between the first edge LSR and the non-MPLS network. This ingress gateway receives label requests from the first edge LSR. These label requests are multicast to several egress gateways. At least one egress gateway sends a message back indicating that it can transmit data to the destination. In response, the ingress gateway designates that egress gateway to be a designated gateway. The egress gateway then establishes a tunnel through the non-MPLS network to the ingress gateway.

A method for managing virtual links within a multiple protocol label switched network is provided. A virtual link which includes a set of links between two devices is regarded as a single entity by a control component of a label switching router. Each packet to be transported on the virtual link is labeled based on its assigned forwarding equivalence class. A specific label is bound to a corresponding forwarding equivalence class. Such packets can be forwarded onto any one of the links within the virtual link. To load balance the various links within the virtual link, different selected hash functions are used at selected times to apportion the packets. depending on the load conditions.

The present invention sets forth a methodology for providing improved downlink backhaul services from a radio network controller (RNC) to a plurality of base stations via a backhaul network that provides Ethernet services. The Ethernet services are provided by a group of provider edge (PE) switches and regular label switch routers (referred to as P switches). Base stations within the network are assigned into clusters, each of the clusters having a cluster ID. The RNC transmits packets to a given switch or switches out on the network based on a cluster ID included within the transmitted packet. The communications traffic is then multicast from at least one last hop switch in the network to candidate base stations on the basis of the cluster ID and an active set within the cluster. Advantageously, the clusters act as subgroups for more easily directing the transmission of the backhaul multicast traffic. Significant advantages are realized through use of the present invention, including the ability to allow faster and smoother handoffs, as well as backhaul bandwidth savings since intelligence regarding cell switching is extended out at a point farther along the network than was previously enabled.

A technique triggers packing of path computation requests (PCRs) for traffic engineering (TE) label switched paths (LSPs) that are sent from one or more label-switched routers (LSRs) to a path computation element (PCE) of a computer network. According to the novel technique, incoming PCRs are packed into sets in response to a certain event, and one or more TE-LSPs (paths) are computed for each PCR of a particular set based on the PCRs of that set. Specifically, the PCE detects an event in the network (“network event”) indicating that an increase in the number of incoming PCRs has occurred, or that an increase is likely to occur due to, e.g., a change in a network element. Once the net-work event has been detected, the PCE packs the incoming PCRs into configured-length sets, such as, e.g., for a specified time interval or a certain number of PCRs. The PCE computes paths for each PCR of a particular set while considering the other PCRs of that set, thereby reducing race conditions, signaling overhead, and set-up failures.

The present invention discloses a method for applying a multi-protocol label switching (MPLS) network in general packet radio service (GPRS). The MPLS network is established by multiple differentiated service (DS) domains. Each DS domain is constructed by multiple label switching routers (LSRs) and label edge routers (LERs). The LER provides at least a service GPRS supporting node (SGSN) connected to a wireless network base station, and a gate GPRS supporting node (GGSN) connected to a packet switching network. At a signalling plane, IP addresses of all SGSNs and GGSNs are utilized to establish all one-to-one pre-created label switching paths (LSPs) in the MPLS network of the GPRS backbone network. At a transmission plane, the pre-created LSP and LSP tunneling transmit packets between SGSN and GGSN.

Disclosed is a technique which reduces the packet loss and the band consumption for data transfer when a mobile terminal conducts the handover between a fixed base station and a mobile base station for group movement. According to this technique, when an MH (mobile terminal) 320 conducts the handover from a fixed base station (E-LSR 230) positioned at an edge of an access network 200 to a mobile base station (MEB 310) located in a train or the like, a predetermined flag is appended to a frame addressed to the MH in a label switching router (P-LSR 210) positioned at a core network 100 side edge of the access network. The frame having the appended flag is copied in the E-LSR 230. One frame after copied is transmitted directly from the E-LSR to the MH while the other frame after copied is transferred from the E-LSR to the MEB and then transmitted from the MEB to the MH, thus realizing the soft handover.

The invention discloses a failure detection method, a communication system and a label switching router, aiming at overcoming the problem that BFD message analysis failure detection to a plurality of nodes cannot be realized in the prior art. The method comprises the following steps: the hop number between a first node and a second node on a main LSP is determined, and the second node is positioned at the downstream of the first node; a BFD message is encapsulated into a MPLS message which carries the hop number between the first node and the second node; the MPLS message is sent out along the main LSP from the first node; the node receiving the MPLS message judges if the node is the second node according to the hop number, if so, the node extracts the BFD message for detection so as to obtain a failure detection result, otherwise, the node transmits the MPLS message. By adopting the technical proposal of the invention, the failure detection in the MPLS can be more flexible.

The invention discloses a method and device for protecting a router. According to the invention, the configuration of a backup path for an end-to-end link between LSRs (Label Switching Router) is realized, and a corresponding forwarding item is established, therefore, the backup path can be used for protecting multiple arbitrary LSPs (Label Switched Path) on the link. Compared with the prior art, the invention has the advantages that the item capacity established through the technical scheme is fewer with more protected LSPs; and moreover, the tail node of the corresponding backup path is definite, which is more convenient to configure the protection switch mechanism of a network.

The present invention provide a report approaches and transmit Label Switching router based on the tunnel, the entrance of the tunnel has been built Label Switching Router (LSR), the as-built tunnel export LSR and non-tunnel has been built in LSR posed by the Channel tunnel Label Switching (LSP) static allocation, and configuration LSR tunnel entrance has been built, the tunnel will have built their own entrance LSR reach the path downstream equipment identification information has been set to build the tunnel information, the establishment of the new tunnel completed; When the new tunnel needed to transmit text, in accordance with the method of transmitting LSP Tunnel text was transmitted, and arrived at the tunnel has been built the entrance LSR, in accordance with the entrance of the tunnel has been built LSR reach their downstream equipment will be on the path to the text information from as-built tunnel transponders until the new tunnel export LSR. Application of this invention program, the tunnel can be built into the new tunnel, so that we can effectively use the tunnel has been built to save the tunnel resources.

The invention provides a detection method of a label switching path (LSP) and a label switching router. The detection method comprises the steps of: when carrying out fault detection on the LSP corresponding to an FEC (Forward Error Correction) code with a destination address being a same network segment IP address, after inquiring next hop information corresponding to the network segment IP address in a local route list by an inlet LSR (Launch Signal Responder) of the LSP, sending the BFD message to the outlet LSR corresponding to the next hop information; and after any one LSR in the LSP receives a BFD (Bidirectional Forwarding Detection) message, if recognizing that the LSR is not the outlet LSR of the LSP, inquiring next hop information corresponding to the network segment IP address in the local route list and forwarding the BFD message according to the inquired next hop information until the BFD message is sent to the outlet LSR of the LSP. The invention overcomes the defect that the traditional BFD detection technology is only capable of detecting the LSP corresponding to the FEC with the destination IP address being a host computer IP address, and successfully realizes the BFD detection on the LSP corresponding to the FEC with the destination IP address being the network segment address.

The present invention discloses a method for preventing label switch path oscillating and an interim LSR. In the method, when LDP session of the interim LSR is down in downstream, releasing an FEC-label binding relationship from the LDP session, a interim LSP corresponding to the released FEC-label binding relationship is switched as agent outlet and maintained for a period of time, and updating the transmitting item to keep normal transmission. If maintenance time of the agent outlet LSP exceeds a preset time, then repealing the agent outlet LSP; if the LDP session returns to normal before maintenance time of the agent outlet LSP exceeds a preset time, then reverting the agent outlet LSP to an interim LSP according to a re-announced FEC-label binding relationship of the downstream LDP neighbor, and updating the transmission item again. In this way, when a downstream session of the interim LSP is oscillating, repeated repealing and creation of the LSP is prevented.

The embodiment of the invention discloses a method for advertising an adjacent network domain of DS-TE information, which comprises the steps of detecting whether the DS-TE information of a network domain and the adjacent network domain changes or not and carrying out advertisement in the network domain by link-state advertisement (LSA) when detecting that the DS-TE information of the network domain and the adjacent network domain changes. The embodiment of the invention also discloses a system and a device for advertising the adjacent network domain of the DS-TE information. By the method, the system and the device for advertising the adjacent network domain of the DS-TE information, an ingress label switching router (ingress LSR) or a path calculating element (PCE) can learn about the DS-TE information of the adjacent network domain.

The invention discloses a method for establishing a cross-domain LSP (Label Switching Path). The method comprises the following steps: after a target address corresponding to a forwarding equivalence class FEC is obtained by a label edge router (LER), if a longest matching route of the target address is searched locally, transmitting label REQUEST information of FEC to a next hop of label switching router (LSR) corresponding to the longest matching route; after the label request REQUEST information of FEC is received by LSR, if a longest matching route of the target address of the FEC is searched locally, transmitting label REQUEST information of FEC to a next hop of LSR corresponding to the longest matching rout or transmitting label MAPPING information of FEC to LER or LSR for transmitting the label REQUEST information of FEC. The invention further discloses a system and a device for establishing the cross-domain LSP, and a method, a system and a device for removing the cross-domain LSP, by adopting the invention, the problem of incapability of establishing or removing the cross-domain LSP under a DOD (Downstream On Demand) label distribution mode by the conventional seamless MPLS (Multi-Protocol Label Switching) network end-to-end device.

A method of setting a path in a network using an Internet protocol to facilitate voice communications between two devices includes determining whether a first path having an adequate bandwidth for transferring a voice over Intent protocol (VoIP) packet between two label switch routers exists. The method also includes setting a new path having a bandwidth that is at least two times the necessary bandwidth for transferring a VoIP packet, when it is determined that the first path does not exist.

The invention provides a method for realizing label switching path (LSP) switching and a device. When the method and the device are used, after a link is broken, an upstream end label switching router (LSR) can carry a work LSP of a downstream end LSR at the inner layer of a message so that the downstream end LSR can be identified, and in addition, a label arranged on a protection ring is carried on the outer layer of the message so that the message can be transferred to the downstream end LSR through the protection ring. Therefore, a part of the broken link in the work LSR can be switched to the protection ring so that the message reaches the downstream end LSR by bypassing the broken link through the protection ring, and finally, after the label arranged on the protection ring of the outer layer of the message is ejected out by the downstream end LSR, the transferring can be normally carried out at the rest part of the work LSP through starting at the downstream end LSR.

Disclosed is a technique which reduces the packet loss and the band consumption for data transfer when a mobile terminal conducts the handover between a fixed base station and a mobile base station for group movement. According to this technique, when an MH (mobile terminal) 320 conducts the handover from a fixed base station (E-LSR 230) positioned at an edge of an access network 200 to a mobile base station (MEB 310) located in a train or the like, a predetermined flag is appended to a frame addressed to the MH in a label switching router (P-LSR 210) positioned at a core network 100 side edge of the access network. The frame having the appended flag is copied in the E-LSR 230. One frame after copied is transmitted directly from the E-LSR to the MH while the other frame after copied is transferred from the E-LSR to the MEB and then transmitted from the MEB to the MH, thus realizing the soft handover.