Telefonaktiebolaget Lm Ericsson (publ)

Juniper Networks, Inc.

Other

Antoni Bronislaw Przygienda

Evgeny Tantsura

Pramodh D'Souza

Alia Karin Atlas

Lars Ernstrom

Russ White

Shraddha Hegde

Gert Grammel

Ramanathan Lakshmikanthan

Gregory Mirsky

Albert Jining Tian

Harsha Lakshmikanth

Salih K A

V S Jagannadham (Jack) Jonnalagadda

Christopher Bowers

Prasanna Chalapathy

Zoltan Toth

Sajjad Ahmed

A secure IGP topology or other link state topology can be implemented by a network security unit that runs in a centralized environment on servers separate from a network associated with the IGP topology. The network security unit acquires the topology information, such as by participating in IGP or through border gateway protocol with link state (BGP-LS). The network security unit detects possible network problems, such as indicators of potential network attacks. Once an indicator of a potential network attack is detected, the network security unit identifies the node that is compromised. Once the compromised node is identified, the network security unit can report the node for manual or automated intervention. In some aspects, the network security unit can isolate the compromised node by shutting down links connected to the compromised node.

Secure network topology

Problems associated with providing a large Clos network having at least one top of fabric (ToF) node, a plurality of internal nodes, and a plurality of leaf nodes may be solved by: (a) providing L2 tunnels between each of the leaf nodes of the Clos and one or more of the at least one ToF node to ensure a non-partitioned IGP L2 backbone, and (b) identifying the L2 tunnels as non-forwarding adjacencies in link state topology information stored in ToF node(s) and leaf node(s) such that the L2 tunnels are not used for forwarding traffic. Tunnel formation is prevented over L2.

Defining non-forwarding adjacencies in bipartite networks, such as Clos networks, having a level 2 backbone and level 1 nodes

Problems associated with providing a large Clos network having at least one top of fabric (ToF) node, a plurality of internal nodes, and a plurality of leaf nodes may be solved by: (a) providing L2 tunnels between each of the leaf nodes of the Clos and one or more of the at least one ToF node to ensure a non-partitioned IGP L2 backbone, and (b) identifying the L2 tunnels as non-forwarding adjacencies in link state topology information stored in ToF node(s) and leaf node(s) such that the L2 tunnels are not used for forwarding traffic. In some example implementations consistent with the present disclosure, the L2 tunnels are not used to compute routes from the link state topology information. Alternatively, in some other example implementations consistent with the present disclosure, the L2 tunnels are used to compute routes, but such routes are not used, or only used if no routes using only L1 (or L1-down adjacencies) are available. In some example implementations consistent with the present disclosure, L2 prefix information is leaked down to L1 of the IGP.

Defining non-forwarding adjacencies in bipartite networks, such as Clos newtorks, having a level 2 backbone and level 1 nodes

A method includes receiving, by a first network device, messages from a plurality of network devices in a network, each of the messages indicating a level value of a respective sending network device in a network topology, determining, by the first network device and based on the respective levels indicated by the messages, a level value of the first network device in the network topology, determining, by the first network device and based on the determined level value, a mechanism by which to forward network traffic to one or more of the plurality of network devices, and forwarding the network traffic according to the determined mechanism.

Reduced configuration for multi-stage network fabrics

Methods and apparatuses for fast convergence in Layer 2 overlay network are described. Forwarding of Layer 2 (L2) traffic addressed to one or more remote L2 destinations is performed according to a remote L2 (RL2) instance, where the RL2 instance identifies a primary path for forwarding the traffic towards the remote L2 destinations, and a provider edge service label (PESL) instance associated with a broadcast domain including one or more network devices for forwarding the L2 traffic towards the L2 destination, and where the PESL instance is identified with a unique immutable PESL instance label. In response to a network event, an update of the RL2 instance is performed. The update results in an update of a data plane for forwarding the L2 traffic without necessitating an update of forwarding table entries for each one of the one or more remote L2 destination.

Fast control path and data path convergence in layer 2 overlay networks

In response to a connectivity disruption in an underlying optical transport ring supporting a routing and packet switching topology, one or more of optical devices of the optical transport ring are modified to establish connectivity between spine nodes in different data centers to reroute communication between at least a subset of the leaf network devices so as to traverse an inter-spine route via the optical modified optical transport ring. That is, in response to a connectivity disruption in a portion of underlying optical transport ring, one or more optical devices within the optical transport ring are modified such that packets between at least a portion of the leaf devices are rerouted along optical paths between at least two of the spine network devices.

Data center packet optical transport failure protection

Exemplary methods include a first network device participating in an election process to determine a designated bit forwarding router (D-BFR). The methods include in response to determining the first network device is elected to be the D-BFR, performing D-BFR operations comprising assigning one or more bitmask positions (BMPs) to one or more bit forwarding egress routers (BFERs) and advertising the assigned one or more BMPs. The method may further include one or more of determining an elected bitmask (BM) length based on maximum local BM lengths advertised by other BFRs and determining an elected tree type based on supported tree types advertised by other BFRs.

Automated determination of tree attributes and assignment of receiver identifiers by distributed election in multicast architectures relying on packets identifying intended receivers

The disclosed method may include (1) establishing a communication session between a plurality of network nodes to enable the plurality of network nodes to exchange route updates with one another, and then during the communication session, (2) detecting, at one of the network nodes, at least one route update to send to another one of the network nodes, (3) compressing, at the network node, the route update to reduce an amount of data included in the route update, and then upon compressing the route update, (4) sending the compressed route update to the other network node to enable the other network node to forward traffic along a path whose route is advertised in the compressed route update. Various other methods, systems, and apparatuses are also disclosed.

Method, system, and apparatus for reducing the size of route updates

The disclosed method may include (1) identifying, at a first node, a preconfigured level of the first node, (2) receiving, at the first node from a second node, a neighbor advertisement that includes a preconfigured level of the second node, (3) determining that a difference between the preconfigured level of the first node and the preconfigured level of the second node is equal to one, (4) recording, at the first node based on the difference being equal to one, an adjacency relationship between the first node and the second node, (5) transmitting a first type of routing-protocol packet from the first node to the second node based on the adjacency relationship, and (6) refraining from transmitting a second type of routing-protocol packet from the first node to the second node based on the adjacency relationship. Various other apparatuses, systems, and methods are also disclosed.

Apparatus, system, and method for distributing routing-protocol information in clos fabrics

A method is implemented by a network device functioning as a provider edge (PE) device to determine a designated forwarder (DF) for sending broadcast, unknown unicast or multicast (BUM) traffic to a customer edge (CE) device, which is connected to a plurality of PE devices in an Ethernet virtual private network (EVPN) instance on a given Ethernet segment. The method reduces a time for DF determination and loss of traffic for the CE device. The method determines whether a number of active links from the network device to the CE device is greater than an active link minimum. The method also determines that the network device is the DF in response to determining that the number of active links is greater than the active link minimum.

Designated forwarder (DF) election and re-election on provider edge (PE) failure in all-active redundancy topology

Exemplary methods performed by a first network device (ND) include generating first and second prefix entries associating incoming Internet Protocol (IP) traffic to first and second data structures (DSs), respectively. Generating the first DS includes generating a first proxy including forwarding information causing incoming IP traffic to be forwarded to a second ND, and generating a second proxy referencing a third DS. Generating the second DS includes generating a first proxy including forwarding information causing incoming IP traffic to be forwarded to the second ND, and generating a second proxy referencing the third DS. The methods include generating the third DS including forwarding information causing the incoming IP traffic to be forwarded to a third ND, the third DS further including first state information indicating whether the forwarding information included in the first proxies of the first and second DSs should be used for forwarding the incoming IP traffic.

Method and apparatus for optimal, scale independent failover redundancy infrastructure

Exemplary methods include generating a first fast reroute (FRR) next hop (NH) comprising of a first primary next hop (PNH), a first secondary next hop (SNH), and a first attribute, wherein the first PNH and first SNH include forwarding information that causes traffic to be forwarded towards a second and third network device, respectively. The methods include sending a first request to a forwarding plane to generate a second FRR NH comprising of a second PNH, a second SNH, and a second attribute. The methods include updating contents of the first FRR NH, and sending a second request to the forwarding plane to update the second FRR NH, wherein the second request causes the forwarding plane to determine whether to revert back to using the second PNH based on whether the first attribute included in the second request is different from the second attribute of the second FRR NH.

Method and apparatus for fast reroute, control plane and forwarding plane synchronization

Exemplary methods include a first network device participating in an election process to determine a designated bit forwarding router (D-BFR). The methods include in response to determining the first network device is elected to be the D-BFR, performing D-BFR operations comprising determining an elected bitmask (BM) length of a BM based on maximum local BM lengths advertised by other BFRs in the network, wherein each bit of the BM will correspond to a bit forwarding egress router (BFER), and advertising the determined elected BM length to other BFRs. The methods may further include one or more of determining an elected tree type based on supported tree types advertised by other BFRs in the network, assigning one or more BM positions (BMPs) to one or more BFERs, and advertising the elected determined tree type and/or the assigned one or more BMPs.

A network device executes a method to forward a packet that is encoded using an explicit list encoding of sparse multicast group membership information with Bit Index Explicit Replication. The method includes receiving a packet that includes a bitstring having a list of Bit Forwarding Router IDs (BFR-ids). The method further includes selecting a BFR-id identifying a destination Bit Forwarding Router (BFR) from the list for processing, looking up a forwarding bitmask for the destination BFR and a next-hop to reach the destination BFR in a bit index forwarding table, creating a copy of the packet, clearing the selected BFR-id from the packet, clearing BFR-ids from the packet and the copy of the packet based on the forwarding bitmask, and forwarding the copy of the packet to the next-hop neighbor.

Explicit list encoding of sparse multicast group membership information with Bit Index Explicit Replication (BIER)

A method and system provides for path maximum transmission unit (PMTU) discovery (PMTUD) for a multicast distribution implemented in a network using bit indexed explicit replication (BIER) architecture. The network has a set of bit forwarding routers (BFRs) that form a BIER domain including at least one ingress BFR (BFIR) and a set of egress BFRs (BFERs). The method improves efficiency of the PMTUD by limiting probe packet traffic. The method includes selecting a BFER from the set of BFERs in the BIER domain to be processed, generating a probe packet to the selected BFER using a current MTU, sending the probe packet to the selected BFER, and updating the current MTU and adding BFERs identified by a response to the probe packet to the set of BFERs in the BIER domain to be processed.

Growing community of inventors

Sunnyvale, CA, United States of America

Antoni Bronislaw Przygienda