84 results about "Forwarding equivalence class" patented technology

A method and apparatus for selecting paths to route incoming traffic through a data communication network, which is capable of effectively dispersing the traffic load to the selected paths on the network and effectively optimizing the use of network resources. In a communication network, a plurality of label switched paths between an ingress node and an egress node are provided. Incoming traffic at the ingress node is labeled and delivered through the network to the egress node. In a method and apparatus for selecting paths to route the incoming traffic through the network, a plurality of forwarding equivalent class elements (FEC) of the incoming traffic at the ingress node are allocated for the plurality of label switched paths. The labeled traffic is delivered on the plurality of label switched paths on an FEC-element basis so as to route the labeled traffic through the network to the egress node. The traffic load on the respective label switched paths can be effectively dispersed and the sequence of data packets, sent by the same terminal, may be maintained.

A Fast Reroute implementation where switchover time to backup tunnels upon failure of a protected network element is independent of a number of entries corresponding to forwarding equivalence classes forwarding over LSPs using that element. During normal operation of a packet forwarding device, adjacency information for a received packet is retrieved from a forwarding table based on a look-up of the packet's forwarding equivalence class. Upon failure of a link or node, the appropriate entries in this forwarding table are rewritten to implement the switchover to preconfigured backup tunnels. The switchover is effective even before the rewrite process has completed. Upon detection of the failure, forwarding processing shifts to a fix-up mode. During the fix-up mode, the look-up to the previously mentioned forwarding table is followed by a look-up to a backup tunnel adjacency table based on a pointer retrieved from the forwarding table. Operations relating to use of this backup tunnel adjacency table increase forwarding time somewhat but only during the special fix-up mode.

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.

An ingress multi-protocol label switching (MPLS) label switched router (LSR) forwards a set of packets associated with a first set of forwarding equivalence classes (FECs) along a label switched path (LSP) to an egress MPLS LSR. Logic in the ingress MPLS LSR produces an operation and maintenance (OAM) connectivity verification probe message encoding the first set of FECs, and forwards the OAM connectivity verification probe message along the LSP to the egress MPLS LSR. Logic in the egress MPLS LSR produces an encoding of a second set of FECs. Logic in the egress MPLS LSR compares the encoding of the first set of FECs in the connectivity verification probe message to the encoding of the second set of FECs, and produces an indication if the comparison indicates that the first set of FECs is not a subset of the second set of FECs.

An ingress multi-protocol label switching (MPLS) label switched router (LSR) forwards a set of packets associated with a first set of forwarding equivalence classes (FECs) along a label switched path (LSP) to an egress MPLS LSR. Logic in the ingress MPLS LSR produces an operation and maintenance (OAM) connectivity verification probe message encoding the first set of FECs, and forwards the OAM connectivity verification probe message along the LSP to the egress MPLS LSR. Logic in the egress MPLS LSR produces an encoding of a second set of FECs. Logic in the egress MPLS LSR compares the encoding of the first set of FECs in the connectivity verification probe message to the encoding of the second set of FECs, and produces an indication if the comparison indicates that the first set of FECs is not a subset of the second set of FECs.

A method and system for forwarding data units in a communications system, that comprises: ingress routers (901) capable of forwarding data units and containing a Forwarding Equivalence Class table (911) that contains mapping information, intermediate routers (905, 907, 909) capable of forwarding data units, egress routers (903) capable of forwarding data and containing a Forwarding Equivalence Class table (919) that contains mapping information. The method comprising the steps of: assigning a first label on data unit and a second label on data unit based on mapping information, sending data unit in to egress router via one or more intermediate router (905, 907, 909), receiving (903) data unit, identifying data unit based on mapping information on Forwarding Equivalence Class table (919) and based on second label. The method further comprises the steps of: creating a Forwarding Equivalence Class for radio access network specific data units; and storing information about Forwarding Equivalence Class in Forwarding Equivalence class table (FEC).

There is disclosed an apparatus and method for limiting tunnel traffic in a network. Traffic engineering tunnels are used to direct traffic along a predefined path, which may differ from the path that internet protocol (IP) routing would determine. Interior gateway protocol (IGP) cut through will allow the forwarding of all destinations downstream of a tunnel through the tunnel, without the operator needing to specify a forwarding equivalence class (FEC). But congestion in the tunnel and network instability may result from this approach. A solution to these problems is disclosed which limits the traffic in the tunnel to only that with destination addresses of the tunnel's egress router or nodes directly supported thereby. Other solutions are disclosed which allow tunnel traffic to nodes having destination addresses other than those being directly supported by the tunnel's egress router. All of these solutions are achieved in both pre-determined forwarding entry and dynamic packet-by packet embodiments.

A Fast Reroute implementation where switchover time to backup tunnels upon failure of a protected network element is independent of a number of entries corresponding to forwarding equivalence classes forwarding over LSPs using that element. During normal operation of a packet forwarding device, adjacency information for a received packet is retrieved from a forwarding table based on a look-up of the packet's forwarding equivalence class. Upon failure of a link or node, the appropriate entries in this forwarding table are rewritten to implement the switchover to preconfigured backup tunnels. The switchover is effective even before the rewrite process has completed. Upon detection of the failure, forwarding processing shifts to a fix-up mode. During the fix-up mode, the look-up to the previously mentioned forwarding table is followed by a look-up to a backup tunnel adjacency table based on a pointer retrieved from the forwarding table. Operations relating to use of this backup tunnel adjacency table increase forwarding time somewhat but only during the special fix-up mode.

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.

When a MPLS Virtual Forwarding Entity (VFE) on a Link State Protocol Controlled Ethernet Network learns a forwarding equivalency class (FEC) to label binding from an attached MPLS-LER, it will determine an associated MAC address for the FEC, and advertise the FEC / label binding along with the MAC address. Nodes in the Ethernet network will install shortest path forwarding state for the MAC to the MPLS-VFE advertising the FEC / label binding. Each MPLS-VFEs on the Ethernet network that receive the advertisement will update its database and generate a label that is distributed to attached MPLS LERs using LDP. When the MPLS-LER needs to transmit traffic to the FEC, it will use the label provided by the MPLS-VFE. The MPLS-VFE maintains a mapping between the label and the MAC address so that it may use the MAC address to forward the packet across the Ethernet network.

A data structure for implementing a traffic engineering function in a multiprotocol label switching system comprises: a subscriber profile including a plurality of entries for storing forwarding equivalence class (FEC) information required for setup of a label switched path (LSP) based on the traffic engineering function, the entries of the subscriber profile being sequentially assigned indexes corresponding to one traffic engineering service subscriber identification (ID); a path profile including a plurality of entries for storing respective path information items regarding a type length value (TLV) of a signal protocol required for setup of an explicit routed label switched ath (ER-LSP) based on the traffic engineering function, the entries of the path profile being sequentially assigned indexes corresponding to respective path information items; and a quality of service (QoS) profile including a plurality of entries for storing respective QoS information items regarding a TLV of a signal protocol required for setup of a constraint routed label switched path (CR-LSP) based on the traffic engineering function, the entries of the QoS profile being sequentially assigned indexes corresponding to respective QoS information items. The indexes assigned to the profile entries include a plurality of indexes set by an operator for interlinking corresponding ones of the subscriber profile entries, the path profile entries, and the QoS profile entries.

The invention discloses a method and a system for establishing a label switched path and a label switching router, and belongs to the field of communication. The method comprises the following steps: sending a label request message which carries attribute sign information of an equivalent multi-path router of an forwarding equivalence class to a downstream node by a node on the edge of an inlet, sending the label request message to a next hop node according to the attribute sign information by the downstream node receiving the label request message; and performing label mapping according to a path of the label request message by the node receiving the label request message, performing label binding for the forwarding equivalence class, and establishing the label switched path. The method avoids establishing the equivalent multi-path router for the forwarding equivalence class with a special requirement through the introduction of the attribute sign information for establishing the equivalent multi-path router or not in the process of establishing the label switched path, thereby contributing to network management and maintenance.

The present invention provides a method of supporting a multi-port virtual local area network (VLAN) with a multi-protocol Label switch (MPLS), comprising steps of: establishing a label switching path (LSP) by the label distribution protocol (LDP), and obtaining information binding a forwarding equivalence class (FEC) and a label or information binding an ingress label and an egress label, and an address of a LDP peer entity at an opposite end, which is a next-hop IP address; the MPLS table item managing module creating a forwarding-relation table, and adding a forwarding-relation table item based upon the obtained information; obtaining an egress port corresponding to the forwarding-relation table item based upon the next-hop IP address; and accomplishing the MPLS via the egress port. With the present invention, it is possible to support the multi-port VLAN in a three-layer switch with the function of the MPLS and implement the MPLS in the VLAN.

A Fast Reroute implementation suitable for use in a label switched router. Reroute from protected tunnels to backup tunnels may be achieved in constant time irrespective of the numbers of protected forwarding equivalence classes and protected tunnels.

New layer of data link layer protocol - data link procedure (DLP) is introduced between IP of network layer and each physical layer in the invention in order to overcome shortage of current method of intercommunication between IPv4 network and IPv6 network. Using DLP defined destination address code and source address code expresses forwarding equivalence class of IP address and source address of IP packet. Using forwarding equivalence class of IP packet as addresses in data link layer realizes forwarding and exchanging IP packets in two layers so as to realize intercommunication between IPv4 network and IPv6 network in data link layer. Features are: high efficiency of forwarding IP packets, safety and reliability, flux engineering capability, 50 ms protected rearrangement function, compatible to packet voice network. The method makes current IP network transits to united telecom public network in next generation smoothly.

The invention discloses a method for ensuring bidirectional forwarding detection reliability and label switching path equipment. Source end equipment transmits a multiprotocol label switching (MPLS) label switching path (LSP) PING request message carrying route identification information to host end equipment, and the host end equipment uniquely determines bidirectional forwarding detection (BFD) session according to the route identification information in the MPLS LSP PING request message and forwarding equivalence class (FEC). In the invention, the existing MPLS LSP Ping standard RFC4379 is expanded, and MPLS Router ID TLV (Threshold Limit Value) is added for carrying the parameter (i.e. Router ID) for uniquely determining the BFD session. On the basis of being compatible with the existing standard, the method in the invention proposes a complete solution of LSP BFD, and the problem of abnormal BFD session detection is solved in case that the forwarding path varies in the existing solution.

The label distribution protocol (LDP) is extended to set up a point to multi-point (P2MP) label switched path (LSP) across a computer network from a source network device to one or more destination network devices. LDP is extended to create a P2MP label map message containing a label and a P2MP forwarding equivalence class (FEC) element having a root node address and an identifier. The P2MP FEC element may, for example, associate an address of the root node of the P2MP LSP with an opaque identifier. The P2MP FEC element uniquely identifies the P2MP LSP. The P2MP FEC element may be advertised with a label in a P2MP label map message. A source network device or the destination network devices may initiate setup and teardown of the P2MP LSP. The P2MP label map messages may be propagated from the destination network devices to the source network device.

The invention provides a forwarding method and a forwarding device for multicast data messages based on a multiple protocol label switching (MPLS). The method includes that specialized multicast labels are assigned to multicast forwarding equivalence class (FEC) of a multicast transmission path, the multicast labels are notified to all nodes of the multicast transmission path; when each of the multicast labels assigned to the multicast FEC are obtained by each of nodes in multicast transmission path, a multicast label forwarding table related to the multicast labels and corresponding to a multicast forwarding table of the multicast FEC is established; and the multicast data messages forwarding are performed according to the multicast label forwarding table. According to the forwarding method and the forwarding device for the multicast data messages based on MPLS, the forwarding efficiency of the multicast data messages can be improved.

Label distribution protocol (LDP) signaled label-switched paths (LSPs) are supported without requiring information about remote autonomous systems (ASs) to be injected into the local interior gateway protocol (IGP). This may be done by (i) decoupling a forwarding equivalency class (FEC) element from the routing information, and (ii) specifying a next hop on which the FEC relies. An LDP messaging structure (e.g., an LDP type-length-value (TLV)) that includes a label, FEC information (e.g., a host address or prefix of an egress LSR of the LSP) and a next hop (e.g., a host address or prefix of a border node, such as an AS border router (ASBR)) may be provided. This messaging structure may be included in one or more of (a) label mapping messages, (b) label withdraw messages, and (c) label release messages. If an LDP message including the expanded LDP messaging structure is received at a node, the node may determine whether or not to propagate the LSP using the next hop information, rather than the FEC information. If, on the other hand, the LDP message includes a normal LDP messaging structure, the node may determine whether or not to propagate the LSP as usual.

The embodiment of the invention discloses a message processing method and system, and devices. The system comprises a controller which is used for allocating service labels to service processing modes of FECs (Forwarding Equivalence Classes), establishing a mapping relationship between the service labels and the service processing modes, sending the service labels to a source node and sending the mapping relationship to a destination node; the source node which is used for receiving the service labels sent by the controller, receiving first messages, inserting the first messages into the service labels to obtain second messages and sending the second messages to the destination node; and the destination node which is used for receiving the mapping relationship sent by the controller, receiving the second messages sent by the source node and popping up the service labels from the second messages according to the mapping relationship to obtain the first messages, wherein the service labels are used for indicating network devices needing to carry out service processing on the second messages to process the second messages according to the service processing modes in a process of forwarding the second messages from the source node to the destination node.

The invention provides a label distribution device used to inform upstream of distributing labels in the label distribution protocol. The device comprises: a carrying and sending unit positioned at the downstream and used to carry a special label type TLV in a label request message sent to the upstream; an analytic unit positioned at the upstream and used to analyze the special label type TLV after the label request message with the special label type TLV is received; and a distribution unit used to distribute the label with corresponding type for forwarding equivalence class according to the field value in the special label type TLV. So an upstream LSR as the penultimate hop of a certain FEC can distribute an implicit null label to the FEC to be taken as an out-label under the upstream label distribution mode, thereby realizing the pop-up of the penultimate hop.

Described herein are various embodiments of a network element to process routing entries in a forwarding information base (FIB) for hosts that are directly attached to a multi-layer network element to encode address resolution protocol (ARP) data into forwarding equivalence class (FEC) entries for the directly attached hosts. One embodiment provides for a network element comprising a control plane including a forwarding agent and a data plane coupled to the control plane. The data plane can include a forwarding engine to forward a unit of network data from an ingress interface to an egress interface. The forwarding agent can be configured to program the forwarding engine with a forwarding information base having data-link layer forwarding data encoded into a network-layer forwarding entry.

The embodiment of thehe present invention discloses a method and apparatus for processing label distribution protocol conversations, and a label switching router. The method includes steps: when discovering addion of a route in a mode of actively distributing DU label on the downstream, enquiring whether a forwarding equivalence class FEC corresponding with the route, sends label canceling messageto a peer and receives a corresponding label releasing message of the label canceling message or not; when the peer has sent the label canceling message and has received the corresponding label releasing message, or does not have sent the label canceling message, distributing a label for the FEC; sending a label mapping message to the peer, wherein the label mapping message includes the FEC and distributed label. The embodiment of the invention is capable of avoiding that forwarding items of the peers are different due to deletion of the route and rapid addition of the route in a DU mode, ensuring normal forwarding of packets, so as to ensure communication service quality effectively.

The invention discloses a label processing method and a device employing the same, relates to the technical field of communication network and aims to solve a technical problem that quantity of MPLS (Multiple Protocol Label Switching) labels in the prior art cannot support network development. The label processing method includes steps that a first network device distributes first labels generated according to first cardinal number labels and remainder labels for the FEC (Forwarding Equivalence Class), wherein an actual label value corresponding to the first cardinal number labels is larger than or equal to 1 mega; the first network device transmits a label notification message to a second network device, wherein the label notification message includes the first cardinal number labels and the remainder labels and is used for the second network device to generate the first labels according to the first cardinal labels and the remainder labels and to establish a corresponding relation of the FEC and the first labels. By adopting the technical scheme provided by the invention, the quantity of the MPLS labels can be increased effectively, so that the development of MPLS technology is facilitated.

The invention discloses an LSR (label switch router) for realizing the FRR (fast re-routing) of an LDP (label distribution protocol). The LSR comprises an IP FRR unit for establishing a backup route and an LDP FRR unit for establishing a backup LSP (label switch path) path, wherein the IP FRR unit is used for notifying a backup next hop LSR on the backup route computed by the local LSR, which takes the target LSR as the FEC (forwarding equivalence class), to the LDP FRR unit; and the LDP FRR unit is used for establishing the backup LSP according to the backup next hop LSR and an FEC-target LSR label sent by the backup next hop LSR. The invention also discloses a corresponding method. By establishing the backup LSP computed by the IP FRR and ensuring the consistence of the backup LSP and the backup route, and the LDP FRR can select the better path and avoid a bad path; and compared with the conventional LDP FRR, the LSR has flexible realization mode, and is free from relying on a backup interface manually configured by a user.

The invention relates to a processing method used for distributing messages by labels and a label exchanging router; wherein, the method comprises the steps as follows: when a message used for informing that the address provided in an address message used for adding addresses is established, whether the address is the next hop address corresponding to the forwarding equivalence class or not is judged; the label mapping message corresponding to the forwarding equivalence class is received in advance; when the address is the next hop address, whether the forwarding equivalence class is added into an FTN list or not is judged; when the forwarding equivalence class is not added into the FTN list, the forwarding equivalence class is added into the FTN list; corresponding FEC is added into the FTN list when the LSR receives the address message before receiving the label mapping announcement message, thus solving the problem that the LSP can not be established when the LSR receives the address message after receiving the label mapping announcement message.

The present invention provides a method of supporting a multi-port virtual local area network (VLAN) with a multi-protocol Label switch (MPLS), comprising steps of: establishing a label switching path (LSP) by the label distribution protocol (LDP), and obtaining information binding a forwarding equivalence class (FEC) and a label or information binding an ingress label and an egress label, and an address of a LDP peer entity at an opposite end, which is a next-hop IP address; the MPLS table item managing module creating a forwarding-relation table, and adding a forwarding-relation table item based upon the obtained information; obtaining an egress port corresponding to the forwarding-relation table item based upon the next-hop IP address; and accomplishing the MPLS via the egress port. With the present invention, it is possible to support the multi-port VLAN in a three-layer switch with the function of the MPLS and implement the MPLS in the VLAN.