Patents by Inventor Chandra Nagarajan

Chandra Nagarajan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10826770
    Abstract: Systems, methods, and computer-readable media for determining a deployment model for deploying rules in a network environment in response to deployment of a contract into the network environment. In some embodiments, a method can include deploying a contract into a network environment. One or more candidate deployment configuration variables can be selected and policy configurations for deploying rules in the network environment as part of implementing policies using the contract can be determined based on the one or more candidate deployment configuration variables. Rule configuration states corresponding to the policy configuration states in the network environment can be identified based on deployment of the one or more contracts in the network environment. Subsequently, a deployment model for implementing the one or more policies in the network environment can be formed based on the policy configurations and the rule configuration states corresponding to the policy configurations.
    Type: Grant
    Filed: July 26, 2018
    Date of Patent: November 3, 2020
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Divjyot Sethi, Chandra Nagarajan
  • Patent number: 10812318
    Abstract: Systems, methods, and computer-readable media for localizing faults in a network policy are disclosed. In some examples, a system or method can obtain TCAM rules across a network and use the TCAM rules to perform an equivalency check between the logical model and the hardware model of the network policy. One or more risk models are annotated with output from the equivalency check and the risk models are used to identify a set of policy objects of the network policy that are likely responsible for the faults. The identified set of policy objects are correlated with various logs of the network. Based on the correlation, specific policy objects of the set of policy objects that are associated with physical-level causes of the fault.
    Type: Grant
    Filed: September 28, 2017
    Date of Patent: October 20, 2020
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Praveen Tammana, Chandra Nagarajan, Pavan Mamillapalli, Ramana Rao Kompella
  • Publication number: 20200252297
    Abstract: Systems, methods, and computer-readable media analyzing memory usage in a network node. A network assurance appliance may be configured to query a node in the network fabric for a number of hardware level entries, stored in memory for the node, that are associated with a concrete level network rule. The network assurance appliance may identify a logical level network intent associated with the concrete level network rule, identify a logical level component of the logical level network intent, and attribute the number of hardware level entries to the logical level component.
    Type: Application
    Filed: April 24, 2020
    Publication date: August 6, 2020
    Inventors: Ramana Rao Kompella, Chandra Nagarajan, John Thomas Monk, Purna Mani Kumar Ghantasala
  • Publication number: 20200228395
    Abstract: Systems, methods, and computer-readable media for localizing faults in a network policy are disclosed. In some examples, a system or method can obtain TCAM rules across a network and use the TCAM rules to perform an equivalency check between the logical model and the hardware model of the network policy. One or more risk models are annotated with output from the equivalency check and the risk models are used to identify a set of policy objects of the network policy that are likely responsible for the faults.
    Type: Application
    Filed: March 25, 2020
    Publication date: July 16, 2020
    Inventors: Praveen Tammana, Chandra Nagarajan, Pavan Mamillapalli, Ramana Rao Kompella
  • Patent number: 10693738
    Abstract: Systems, methods, and computer-readable media for generating switch-level logical models of a network. In some examples, a system can obtain a logical model of a network, such as software-defined network (SDN). The logical model can represent a configuration of objects and object properties defined based on a schema associated with the network. Based on the logical model, the system can generate a rendered logical model of the network and, based on the rendered logical model, generate, for one or more network devices in the network, a respective device-specific representation of the logical model. The respective device-specific representation can project the logical model to a respective network device, such as a switch in the fabric of the network.
    Type: Grant
    Filed: October 17, 2017
    Date of Patent: June 23, 2020
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Chandra Nagarajan, Advait Dixit
  • Patent number: 10686669
    Abstract: Systems, methods, and computer-readable media for collecting node information from a fabric and generating models based on the node information. In some examples, a system can obtain, from one or more controllers in a software-defined network (SDN), a logical model of the SDN, the logical model containing objects configured for the SDN from a hierarchical management information tree (MIT) associated with the SDN and representing configurations of the objects, the hierarchical MIT defining manageable objects and object properties for the SDN, the objects corresponding to the manageable objects. The system can obtain a topological model of a fabric associated with the SDN and, based on the topological model, poll nodes in the fabric for respective configurations at the nodes. Based on the respective configurations, the system can generate a node-specific representation of the logical model, the node-specific representation projecting the logical model on each node.
    Type: Grant
    Filed: July 28, 2017
    Date of Patent: June 16, 2020
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Chandra Nagarajan, Divjyot Sethi, Ramana Rao Kompella
  • Publication number: 20200186426
    Abstract: Systems, methods, and computer-readable media for static network policy analysis for a network. In one example, a system obtains a logical model based on configuration data stored in a controller on a software-defined network, the logical model including a declarative representation of respective configurations of objects in the software-defined network, the objects including one or more endpoint groups, bridge domains, contexts, or tenants. The system defines rules representing respective conditions of the objects according to a specification corresponding to the software-defined network, and determines whether the respective configuration of each of the objects in the logical model violates one or more of the rules associated with that object. When the respective configuration of an object in the logical model violates one or more of the rules, the system detects an error in the respective configuration associated with that object.
    Type: Application
    Filed: February 10, 2020
    Publication date: June 11, 2020
    Inventors: Kartik Mohanram, Chandra Nagarajan, Sundar Iyer, Shadab Nazar, Ramana Rao Kompella
  • Publication number: 20200177456
    Abstract: Systems, methods, and computer-readable media analyzing memory usage in a network node. A network assurance appliance may be configured to obtain reference concrete level rules for a node in the network, obtain implemented concrete level rules for the node from the node in the network, compare the reference concrete level rules with the implemented concrete level rules, and determining that the implemented concrete level rules are not appropriately configured based on the comparison.
    Type: Application
    Filed: January 28, 2020
    Publication date: June 4, 2020
    Inventors: Ramana Rao Kompella, Chandra Nagarajan, John Thomas Monk, Purna Mani Kumar Ghantasala
  • Patent number: 10652102
    Abstract: Systems, methods, and computer-readable media analyzing memory usage in a network node. A network assurance appliance may be configured to query a node in the network fabric for a number of hardware level entries, stored in memory for the node, that are associated with a concrete level network rule. The network assurance appliance may identify a logical level network intent associated with the concrete level network rule, identify a logical level component of the logical level network intent, and attribute the number of hardware level entries to the logical level component.
    Type: Grant
    Filed: July 27, 2017
    Date of Patent: May 12, 2020
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Ramana Rao Kompella, Chandra Nagarajan, John Thomas Monk, Purna Mani Kumar Ghantasala
  • Publication number: 20200099589
    Abstract: Systems, methods, and computer-readable media for discovering a network's topology and health. In some examples, a system can obtain, from at least one of a plurality of controllers on a network, a logical model of the network, the logical model including configurations of one or more objects defined for the network. Based on the logical model, the system can identify a respective location of the plurality of controllers in the network and a plurality of nodes in a fabric of the network. Based on the respective location of the plurality of controllers and plurality of nodes, the system can poll the plurality of controllers and plurality of nodes for respective status information, and determine a health and topology of the network based on the logical model, the respective location, and respective status information.
    Type: Application
    Filed: November 27, 2019
    Publication date: March 26, 2020
    Inventors: Divjyot Sethi, Chandra Nagarajan, Ramana Rao Kompella, Gaurav Gupta, Sundar Iyer
  • Patent number: 10574513
    Abstract: Systems, methods, and computer-readable media for handling failure scenarios during data collection and analysis for assurance. In some examples, a system can obtain a logical model of a network and, based on the logical model, identify a plurality of controllers on the network and a plurality of nodes on a fabric of the network. The system can probe the plurality of controllers and plurality of nodes for respective status information, including respective reachability information, respective login diagnostics information, and/or respective software information. Based on the respective status information, the system can determine conditions at the plurality of controllers and the plurality of nodes and define one or more assurance operations based on the conditions at the plurality of controllers and the plurality of nodes. The system can then perform the one or more assurance operations.
    Type: Grant
    Filed: October 26, 2017
    Date of Patent: February 25, 2020
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Chandra Nagarajan, Divjyot Sethi, Ramana Rao Kompella
  • Patent number: 10560328
    Abstract: Systems, methods, and computer-readable media for static network policy analysis for a network. In one example, a system obtains a logical model based on configuration data stored in a controller on a software-defined network, the logical model including a declarative representation of respective configurations of objects in the software-defined network, the objects including one or more endpoint groups, bridge domains, contexts, or tenants. The system defines rules representing respective conditions of the objects according to a specification corresponding to the software-defined network, and determines whether the respective configuration of each of the objects in the logical model violates one or more of the rules associated with that object. When the respective configuration of an object in the logical model violates one or more of the rules, the system detects an error in the respective configuration associated with that object.
    Type: Grant
    Filed: July 28, 2017
    Date of Patent: February 11, 2020
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Kartik Mohanram, Chandra Nagarajan, Sundar Iyer, Shadab Nazar, Ramana Rao Kompella
  • Patent number: 10554483
    Abstract: Systems, methods, and computer-readable media for performing network assurance in a traditional network. In some examples, a system can collect respective sets of configurations programmed at network devices in a network and, based on the respective sets of configurations, determine a network-wide configuration of the network, the network-wide configuration including virtual local area networks (VLANs), access control lists (ACLs) associated with the VLANs, subnets, and/or a topology. Based on the network-wide configuration of the network, the system can compare the ACLs for each of the VLANs to yield a VLAN consistency check, compare respective configurations of the subnets to yield a subnet consistency check, and perform a topology consistency check based on the topology. Based on the VLAN consistency check, the subnet consistency check, and the topology consistency check, the system can determine whether the respective sets of configurations programmed at the network devices contain a configuration error.
    Type: Grant
    Filed: July 28, 2017
    Date of Patent: February 4, 2020
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Chandra Nagarajan, Kartik Mohanram, Sundar Iyer, Ramana Rao Kompella
  • Patent number: 10554493
    Abstract: Systems, methods, and computer-readable media analyzing memory usage in a network node. A network assurance appliance may be configured to obtain reference concrete level rules for a node in the network, obtain implemented concrete level rules for the node from the node in the network, compare the reference concrete level rules with the implemented concrete level rules, and determining that the implemented concrete level rules are not appropriately configured based on the comparison.
    Type: Grant
    Filed: July 27, 2017
    Date of Patent: February 4, 2020
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Ramana Rao Kompella, Chandra Nagarajan, John Thomas Monk, Purna Mani Kumar Ghantasala
  • Publication number: 20200036593
    Abstract: Systems, methods, and computer-readable media for determining a deployment model for deploying rules in a network environment in response to deployment of a contract into the network environment. In some embodiments, a method can include deploying a contract into a network environment. One or more candidate deployment configuration variables can be selected and policy configurations for deploying rules in the network environment as part of implementing policies using the contract can be determined based on the one or more candidate deployment configuration variables. Rule configuration states corresponding to the policy configuration states in the network environment can be identified based on deployment of the one or more contracts in the network environment. Subsequently, a deployment model for implementing the one or more policies in the network environment can be formed based on the policy configurations and the rule configuration states corresponding to the policy configurations.
    Type: Application
    Filed: July 26, 2018
    Publication date: January 30, 2020
    Inventors: Divjyot Sethi, Chandra Nagarajan
  • Publication number: 20200007495
    Abstract: Systems, methods, and computer-readable media relate to providing a network management service. A system is configured to request first network information from a first component of a network using a public IP address for the first component, wherein the first network information includes private IP addresses for a second component in the network and translate, based on a mapping information for a private IP address space to a public IP address space, the private IP address for a second component to a public IP address for the second component. The system is further configured to request second network information from the second component using the public IP address and provide a network management service for the network based on the second network information.
    Type: Application
    Filed: October 26, 2018
    Publication date: January 2, 2020
    Inventors: Vivek Balamurugan, Chandra Nagarajan, Divjyot Sethi, Chaitanya Velpula, Manvesh Vyas, Ramana Rao Kompella, Pradhap Muthuraman
  • Publication number: 20200004742
    Abstract: Systems, methods, and computer-readable media for identifying and categorizing changes in epoch policies between a first epoch and a second epoch. Epoch network policy data for a first epoch and a second epoch is retrieved. The retrieved epoch network policy data is used to generate hierarchically structured documents to perform epoch network policy comparisons. Epoch diffs products from the epoch network policy comparisons are provided to a user through a searchable aggregated interface.
    Type: Application
    Filed: December 19, 2018
    Publication date: January 2, 2020
    Inventors: Chandra Nagarajan, Divjyot Sethi, Sanchay Harneja, Dhruv Hemchand Jain, Chien-Ju Lo
  • Patent number: 10498608
    Abstract: Systems, methods, and computer-readable media for discovering a network's topology and health. In some examples, a system can obtain, from at least one of a plurality of controllers on a network, a logical model of the network, the logical model including configurations of one or more objects defined for the network. Based on the logical model, the system can identify a respective location of the plurality of controllers in the network and a plurality of nodes in a fabric of the network. Based on the respective location of the plurality of controllers and plurality of nodes, the system can poll the plurality of controllers and plurality of nodes for respective status information, and determine a health and topology of the network based on the logical model, the respective location, and respective status information.
    Type: Grant
    Filed: October 23, 2017
    Date of Patent: December 3, 2019
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Divjyot Sethi, Chandra Nagarajan, Ramana Rao Kompella, Gaurav Gupta, Sundar Iyer
  • Publication number: 20190222485
    Abstract: Systems, methods, and computer-readable media for emulating a state of a network environment for purposes of re-executing a network assurance appliance in the emulated state of the network environment. In some embodiments, a method can include receiving snapshot data for a network environment corresponding to a specific time in the network environment and including network events occurring in the network environment generated by a network assurance appliance. A state of the network environment at the specific time can be emulated using the snapshot data to create an emulated state of the network environment. Subsequently, the network assurance appliance can be re-executed in the emulated state of the network environment corresponding to the specific time and the network assurance appliance can be debugged outside of the network environment based on re-execution of the network assurance appliance in the emulated state of the network environment.
    Type: Application
    Filed: January 17, 2018
    Publication date: July 18, 2019
    Inventors: Divjyot Sethi, Chandra Nagarajan, Advait Dixit, John Thomas Monk, Gabriel Cheukbun Ng, Ramana Rao Kompella, Sundar Iyer
  • Publication number: 20180367413
    Abstract: Systems, methods, and computer-readable media analyzing memory usage in a network node. A network assurance appliance may be configured to query a node in the network fabric for a number of hardware level entries, stored in memory for the node, that are associated with a concrete level network rule. The network assurance appliance may identify a logical level network intent associated with the concrete level network rule, identify a logical level component of the logical level network intent, and attribute the number of hardware level entries to the logical level component.
    Type: Application
    Filed: July 27, 2017
    Publication date: December 20, 2018
    Inventors: Ramana Rao Kompella, Chandra Nagarajan, John Thomas Monk, Purna Mani Kumar Ghantasala