141 results about "Routing domain" patented technology

Packets are routed in a communications network including an infrastructure of packet switching nodes interconnected by packet transport links, and a plurality of access nodes to which a routing path, defined by data held in packet switching nodes located along the routing path, may be directed in the infrastructure for a given network address. Different types of routing updates are used in a single routing domain.

An apparatus for providing reachability in a routing domain of a data communications network having as components nodes and links therebetween for a routing domain—external destination address is described. The apparatus is arranged to advertise destination address reachability internally to nodes in the routing domain and associate a reachability category with said internal advertisement of said destination address reachability.

A system is provided for facilitating assignment of a virtual routing node identifier to a non-routing node. During operation, the system assigns to a non-routing node coupled to a switch a virtual routing node identifier unique to the non-routing node. In addition, the system communicates reachability information corresponding to the virtual routing node identifier to other switches in the network.

A fast reroute (FRR) technique that may be deployed at the edge of a network having first and second edge devices coupled to a neighboring routing domain. If the first edge device detects a node or link failure that prevents it from communicating with the neighboring domain, the first edge device reroutes at least some data packets addressed to the neighboring domain to the second edge device. The second edge device receives the rerouted packets and then forwards the packets to the neighboring domain. Notably, the second edge device is not permitted to reroute the received packets a second time, e.g., upon identifying another inter-domain node or link failure. As such, loops are avoided at the edge of the network and packets are rerouted to the neighboring routing domain faster and more efficiently than in prior implementations.

A fast reroute (FRR) technique is implemented at the edge of a network. In accordance with the technique, if an edge device detects a node or link failure that prevents it from communicating with a neighboring routing domain, the edge device reroutes at least some data packets addressed to that domain to a backup edge device which, in turn, forwards the packets to the neighboring domain. The rerouted packets are designated as being “protected” (i.e., rerouted) data packets before they are forwarded to the backup edge device. To differentiate which data packets are protected and which are not, the backup edge device employs different sets of VPN label values for protected and non-protected network traffic. That is, the backup edge device may allocate two different VPN label values for at least some destination address prefixes that are reachable through the neighboring domain: a first VPN label value for FRR protected traffic and a second VPN label value for non-protected traffic. Upon receiving a data packet containing a protected VPN label value, the backup edge device is not permitted to reroute the packet a second time, e.g., in response to another inter-domain node or link failure, thereby preventing loops from developing at the edge of the network.

A system is provided for facilitating assignment of a virtual routing node identifier to a non-routing node. During operation, the system assigns to a non-routing node coupled to a switch a virtual routing node identifier unique to the non-routing node. In addition, the system communicates reachability information corresponding to the virtual routing node identifier to other switches in the network.

A fast reroute (FRR) technique is implemented at the edge of a computer network. If an edge device detects a node or link failure that prevents it from communicating with a neighboring routing domain, the edge device reroutes at least some data packets addressed to that domain to a backup edge device which, in turn, forwards the packets to the neighboring domain. The backup edge device is not permitted to reroute the packets a second time. According to the inventive technique, the edge device first identifies a group one or more possible backup edge devices and then selects at least one preferred backup edge device from the group. The edge device makes its selection based on the values of one or more metrics associated with the possible backup edge devices. The metrics are input to a novel selection algorithm that selects the preferred backup edge device(s) using a hierarchical selection process or a weighted-metric selection process, or some combination thereof.

A network server provisioning at least one Local Area Network (LAN) comprising a client entry store, a packet driver module, a Dynamic Host Configuration Protocol (DHCP) request handler. The LAN has one or more routing realms. The client entry store stores records representing a user device connecting to the LAN provisioned by the network server as a roaming visitor of the LAN to gain temporal access to an outside network through the LAN, and records representing one or more routing realm top-level devices provided on a top level of each routing realm of the LAN. The packet driver module inspects packets arriving from and directed to the user device, and interacts with the client entry store to process the packets. The DHCP request handler examines address data in DHCP packets received from the user device and the records in the client entry store. At least one of the packet driver module and the DHCP request handler detects roaming between routing realms by the user device based on the data of the packets and the records in the client entry store, and assigns a new Internet Protocol (IP) address to the user device when roaming by the user device is detected.

A fast reroute (FRR) technique is implemented at the edge of a computer network. In accordance with the technique, if an edge device detects a node or link failure that prevents it from communicating with a neighboring routing domain, the edge device reroutes at least some data packets addressed to that domain to a backup edge device which, in turn, forwards the packets to the neighboring domain. The rerouted packets are designated as being “protected” (i.e., rerouted) data packets before they are forwarded to the backup edge device. To that end, the edge device incorporates an identifier into the rerouted data packets to indicate that the packets are being FRR rerouted. The identifier may be a predetermined value stored at a known location in the rerouted packets'encapsulation headers, such as in their MPLS or IP headers. Upon receiving a data packet containing the identifier, the backup edge device is not permitted to reroute the packet a second time.

There is disclosed a system for monitoring a packet data flow, comprising: a data flow source element including: determining means adapted to determine a quality of service identifier for the data flow; first generating means adapted to generate an encoded value in dependence on the quality of service identifier; allocating means adapted to allocate the quality of service identifier and the encoded value to the flow label for each data packet of the data flow; and transmitting means for forwarding data packets including flow labels to a routing domain; and a routing domain interface element including: receiving means for receiving data packets from the data flow source; second generating means adapted to generate a further encoded value in dependence on the quality of service identifier in a flow label of a data packet; comparing means adapted to compare the further encoded value to the encoded value in the flow label; and routing means adapted to selectively route the data packets in dependence on the comparing step.

A local fast reroute (FRR) technique is implemented at the edge of a computer network. In accordance with the technique, if an edge device detects a node or link failure that prevents it from communicating with a neighboring routing domain, the edge device reroutes at least some data packets addressed to that domain to a backup edge device which, in turn, forwards the packets to the neighboring domain. The rerouted packets are designated as being “protected” (i.e., rerouted) data packets before they are forwarded to the backup edge device. The backup edge device identifies protected data packets as those which contain a predetermined “service” label in their MPLS label stacks. In other words, the service label is used as an identifier for packets that have been FRR rerouted. Upon receiving a data packet containing a service label, the backup edge device is not permitted to reroute the packet a second time, e.g., in response to another inter-domain node or link failure, thereby preventing loops from developing at the edge of the network.

A route computation method includes: receiving, by a first bottom-level PCE, a path computation command, performing a route computation on a routing domain managed thereby, obtaining and sending a path segment set with a first node to an upper-level PCE thereof; sending, by the upper-level PCE receiving the path segment set sent by a lower-level PCE, the path computation command to another lower-level PCE according to routing domains that a path to be established between the first node and a second node sequentially passes through, receiving path segment sets sent by all lower-level PCEs, and combining and sending all the received path segment sets to an upper-level PCE thereof, until a top-level PCE receives path segment sets sent by all lower-level PCEs thereof; and combining, by the top-level PCE, all the received path segment sets to generate a set of paths between the first node and the second node.

A system for facilitating bandwidth management in a routing domain (100), the system including: a domain bandwidth manager (116); and a plurality of area bandwidth managers (118, 120, 122, 124, 126, 128) coupled to the domain bandwidth manager and arranged in accordance with an OSPF hierarchical routing topology with the domain bandwidth manager at an upper level of the topology and each area bandwidth manager located in a different area of the routing topology in at least one lower level of the topology, wherein the domain bandwidth manager and the plurality of area bandwidth managers cooperatively coordinate admission control to a routing domain for facilitating a communication session between a source device and a destination device.

A fast reroute (FRR) technique is implemented at the edge of a computer network. If an edge device detects a node or link failure that prevents it from communicating with a neighboring routing domain, the edge device reroutes at least some data packets addressed to that domain to a backup edge device which, in turn, forwards the packets to the neighboring domain. The backup edge device is not permitted to reroute the packets a second time. According to the inventive technique, the edge device first identifies a group one or more possible backup edge devices and then selects at least one preferred backup edge device from the group. The edge device makes its selection based on the values of one or more metrics associated with the possible backup edge devices. The metrics are input to a novel selection algorithm that selects the preferred backup edge device(s) using a hierarchical selection process or a weighted-metric selection process, or some combination thereof.

A method and system for extracting and building end-to-end route information in a two-level, multi-area Internet protocol (IP) autonomous system (AS) operated according to a simple link state routing protocol such as the Integrated System to Integrated System (IS-IS) protocol is disclosed. The method and system enables a user, such as a network administrator, to explicitly identify a full set of paths (links and routers) that a given IP packet would potentially traverse from its entry point in the area of the AS where it originates until its exit point in its intended destination or exit area.

A system is disclosed for providing a platform for optimizing traffic through a computer network having first and second distributed routing domains interconnected through a data center interconnect link. The system comprises one or more servers storing method steps to be executed by the one or more servers. The method steps comprising determining values for QoS characteristics for all routes of traffic routed from first and second routing domains to a destination network and re-rerouting packets from the first routing domain to the second routing domain through the data center interconnect link with better QoS characteristics values than the QoS characteristics values for the first routing domain.

A multicast method for Segment Routing includes, in a Segment Routing network with a plurality of nodes, wherein Segment Routing utilizes globally significant labels as node identifiers such that path state installation is only required at an ingress node of a Segment Routing domain, advertising a multicast flow by a source node; determining roles in the multicast flow for the plurality of nodes; and installing appropriate forwarding behavior for the multicast flow at the plurality of nodes based on the determined roles. The advertising can utilize Interior Gateway Protocol (IGP). For the multicast flow, source node segments are used to construct source routed trees rather than destination-based paths, wherein the source routed trees define broadcast paths, versus destination-based paths which are used in Segment Routing to define a node segment.

The invention relates to a rapid response method for the failure of a link between two routing domains in a packet-oriented network. Once the failure of a link has been identified, substitute routes are provided for the interrupted routes by the local selection of alternative routes and by the propagation of messages along the substitute routes. In contrast to conventional inter-domain protocols such as the BGP (Iborder gateway protocol) the transmission of messages and the associated modification to the routing only involves routing domains that lie along the replacement routes. In one embodiment, a network-wide propagation of messages takes place if the failure of the link represents a persistent breakdown. As a consequence, optimal routes are re-determined in the entire network. The invention provides breakdown compensation that is appropriate for temporary breakdowns and prevents instabilities that occur as a result of the use of conventional inter-domain protocols.

A technique is provided for dynamically discovering shared risk node group (SRNG) memberships of a plurality of interconnected edge devices in a computer network. According to the technique, each edge device “learns” the identities of its directly-attached peer devices situated in neighboring routing domains, e.g., by establishing an interior or exterior gateway routing protocol session with each peer. Thereafter, each edge device advertises the identities of its learned peers to the other interconnected edge devices. Preferably, the peer identities are distributed in novel “peer-router” extended community attributes transported in Border Gateway Protocol (BGP) messages. After an edge device has learned the identity of its own peers and received the identities of the other edge devices' peers, the device can automatically detect SRNG memberships in the computer network. Specifically, edge devices that advertise the same peer are determined to participate in the same SRNG.

A fast reroute (FRR) technique that may be deployed at the edge of a network having first and second edge devices coupled to a neighboring routing domain. If the first edge device detects a node or link failure that prevents it from communicating with the neighboring domain, the first edge device reroutes at least some data packets addressed to the neighboring domain to the second edge device. The second edge device receives the rerouted packets and then forwards the packets to the neighboring domain. Notably, the second edge device is not permitted to reroute the received packets a second time, e.g., upon identifying another inter-domain node or link failure. As such, loops are avoided at the edge of the network and packets are rerouted to the neighboring routing domain faster and more efficiently than in prior implementations.

The method includes following steps: configuring route domain of network and determining boundary nodes and spokesman nodes of route domain; through 'flood' procedure in route protocol, all nodes in route domain obtain full topology information of the route domain; based on configuration information of boundary nodes and network topology information in the route domain, the spokesman nodes generate full connection conglomerate topology of this route domain, and obtain abstracting link of connection between conglomerate topology route and node; calculating available bandwidth attribute of abstracting link; spokesman nodes carries out 'flood' treatment for information of conglomerate topology and abstracting link in route domain in next higher layer. The invention can determine transmitting capacity effectively. Each node obtains transmitting capacity of any route domain in whole network by referring spokesman node of route domain in different layer.

For a managed network including multiple host machines implementing multiple logical networks, some embodiments provide a method that reduces the memory and traffic load required to implement the multiple logical networks. The method generates configuration data for each of multiple host machines including (i) data to configure a host machine to implement a set of logical forwarding elements that belong to a set of routing domains and (ii) identifiers for each routing domain in the set of routing domains. The method then receives data regarding tunnels endpoints operating on each of the host machines and an association with the routing identifiers sent to the host machines. The method then generates a routing domain tunnel endpoint list for each routing domain based on the data received from each of the host machines including a list of the tunnel endpoints associated with the routing domain which the host machines can use to facilitate packet processing.

The invention relates to a network communication technology, in particular to a method for gathering a homologous address beam and a homologous gathering IP (internet protocol) network system. The method comprises: definition for a homologous address related concept, a principle and method for distributing homologous addresses, a method for merging homologous address beams, an algorithm for homologous address gathering, a structure for a homologous address route, a method for generating intra-domain and inter-domain routes based on the homologous addresses, a routing table and transferring table structure using the homologous addresses as inquiry keywords, storage forms of the homologous addresses in a data message, a process for generating a host machine message, and intra-domain and inter-domain transferring processes for the data message based the homologous addresses. Compared with the classless inter-domain routing (CIRD), the invention has the advantages that the defect that CIRD cannot gather a plurality of numerically non-continuous address prefixes is overcome, no preserved 'continuous' address space is required, and the sizes of the routing table and transferring table of each route in a complete route domain are effectively reduced. The network system provided by the invention can more flexibly and better meet customer needs.

A fast reroute (FRR) technique is implemented at the edge of a network. In accordance with the technique, if an edge device detects a node or link failure that prevents it from communicating with a neighboring routing domain, the edge device reroutes at least some data packets addressed to that domain to a backup edge device which, in turn, forwards the packets to the neighboring domain. The rerouted packets are designated as being “protected” (i.e., rerouted) data packets before they are forwarded to the backup edge device. To differentiate which data packets are protected and which are not, the backup edge device employs different sets of VPN label values for protected and non-protected network traffic. That is, the backup edge device may allocate two different VPN label values for at least some destination address prefixes that are reachable through the neighboring domain: a first VPN label value for FRR protected traffic and a second VPN label value for non-protected traffic. Upon receiving a data packet containing a protected VPN label value, the backup edge device is not permitted to reroute the packet a second time, e.g., in response to another inter-domain node or link failure, thereby preventing loops from developing at the edge of the network.

A fast reroute (FRR) technique is implemented at the edge of a computer network. In accordance with the technique, if an edge device detects a node or link failure that prevents it from communicating with a neighboring routing domain, the edge device reroutes at least some data packets addressed to that domain to a backup edge device which, in turn, forwards the packets to the neighboring domain. The rerouted packets are designated as being “protected” (i.e., rerouted) data packets before they are forwarded to the backup edge device. To that end, the edge device incorporates an identifier into the rerouted data packets to indicate that the packets are being FRR rerouted. The identifier may be a predetermined value stored at a known location in the rerouted packets'encapsulation headers, such as in their MPLS or IP headers. Upon receiving a data packet containing the identifier, the backup edge device is not permitted to reroute the packet a second time.

An apparatus and method as described for constructing a repair path for use in the event of failure of an inter-routing domain connection between respective components in first and second routing domains of a data communications network. The apparatus is arranged to assign a propagatable repair address for use in the event of failure of the inter-routing domain connection and to propagate the repair address via data communications network components other than the inter-routing domain connection.

The invention provides a location identifier and host identifier separation-based network system and a mobility management method thereof. The system consists of a core area CA, a routing area RA formed by an organization area OA, a routing area router (RA Router), an organization area router (OA router), a mapping server in the routing area, and various terminals. To simplify the system, functional modules of the mapping server are distributed in routers in the routing area, including the RA router and the OA router, namely a distributed Hash table is used to organize the all RA routers and OA routers in the routing area to store the mapping information between a terminal location identifier, a location identifier of the OA Router connected with the terminal currently, and a host identifier; and from the terminal perspective, the router storing the mapping information of a terminal is called a mapping router Router-M of the terminal. The invention also provides an improved mobility management method on the basis of the network, which supports mobile conversation on the basis of solving the problem of routing expansibility. Furthermore, the invention can be compatible with Internet to reduce the deployment difficulty.

A method includes managing a virtual machine (VM) in a cloud extension, where the VM is part of a distributed virtual switch (DVS) of an enterprise network, abstracting an interface that is transparent to a cloud infrastructure of the cloud extension, and intercepting network traffic from the VM, where the VM can communicate securely with the enterprise network. The cloud extension comprises a nested VM container (NVC) that includes an emulator configured to enable abstracting the interface, and dual transmission control protocol / Internet Protocol stacks for supporting a first routing domain for communication with the cloud extension, and a second routing domain for communication with the enterprise network. The NVC may be agnostic with respect to operating systems running on the VM. The method further includes migrating the VM from the enterprise network to the cloud extension through suitable methods.

The packet switching system for transmitting and receiving a packet via a packet switching network 100, which comprises a plurality of routing tables (#0, #1, #2 . . . ), each of which has been generated by a unique routing policy, stored in the routing apparatuses deployed at the border, at the origin or at the end of the respective routing domains, an identifier (RTI) inserted in the packet to specify the routing tables, and an identifier changer to change a value of the identifier on the packet switching network 100. The routing apparatus selects one of the routing tables (#0, #1, #2 . . . ) according to the RTI in the received packet and transfers the packet to a destination that is specified by the selected routing table.

There is disclosed a system for monitoring a packet data flow, comprising: a data flow source element including: determining means adapted to determine a quality of service identifier for the data flow; first generating means adapted to generate an encoded value in dependence on the quality of service identifier; allocating means adapted to allocate the quality of service identifier and the encoded value to the flow label for each data packet of the data flow; and transmitting means for forwarding data packets including flow labels to a routing domain; and a routing domain interface element including: receiving means for receiving data packets from the data flow source; second generating means adapted to generate a further encoded value in dependence on the quality of service identifier in a flow label of a data packet; comparing means adapted to compare the further encoded value to the encoded value in the flow label; and routing means adapted to selectively route the data packets in dependence on the comparing step.