Patents by Inventor Raghava Sivaramu

Raghava Sivaramu 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: 10284472
    Abstract: In one embodiment, a method includes receiving a request to add a prefix to memory for a route lookup at a forwarding device, the memory comprising a plurality of pivot tiles for storing pivot entries, each of the pivot entries comprising a plurality of prefixes and a pointer to a trie index, searching at the forwarding device, a dynamic pool of the pivot tiles based on a base-width associated with the prefix, allocating at least a portion of the pivot tile to the base-width and creating a pivot entry for the prefix and other prefixes with a corresponding base-width, and dynamically updating prefixes stored on the pivot tiles based on route changes to optimize storage of prefixes on the pivot tiles. An apparatus and logic are also disclosed herein.
    Type: Grant
    Filed: January 24, 2017
    Date of Patent: May 7, 2019
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Nataraj Bacthu, Ayan Banerjee, Raghava Sivaramu, Ankan Ghosh
  • Publication number: 20190097839
    Abstract: Aspects of the disclosed technology address limitations relating to packet replication for multi-destination traffic, by providing methods for performing hardware-based replication in network infrastructure devices, such as switches. In some aspects, application specific integrated circuits (ASICs) resident in physical devices can be used to perform packet replication. Depending on implementation, a hardware-based replication process can include steps for receiving a first packet that includes a first outer header containing first address information, receiving a second packet including a second outer header containing a hardware replication flag, forwarding the first packet to all virtual tunnel endpoints (VTEPs) connected with the TOR switch, and performing hardware replication for the second packet based on the hardware replication flag to generate one or more unicast packets. Systems and machine readable media are also provided.
    Type: Application
    Filed: September 25, 2017
    Publication date: March 28, 2019
    Inventors: Swami Narayanan, Ambrish Mehta, Venkatesh Srinivasan, Raghava Sivaramu, Ayan Banerjee
  • Patent number: 10230623
    Abstract: Disclosed are systems and methods for scaling Massively Scalable Data Center (MSDC) networks with a large number of end-point tunnels utilizing Equal-cost multi-path routing (ECMP). The systems and methods can use the NO-OP label operations to maintain single ECMP objects to switch a set of segment routing tunnels that share the same ECMP links. The forwarding engine can determine the use of the NO-OP label operation and update a received packet to enable the use of the single ECMP objects of the set of segment routing tunnels.
    Type: Grant
    Filed: July 22, 2016
    Date of Patent: March 12, 2019
    Assignee: Cisco Technology, Inc.
    Inventors: Malick Mohamed Usman, Srinivasan Ramabadran, Raghava Sivaramu, Sriram Srinivasan, Srini Ananthakrishnan
  • Publication number: 20180212876
    Abstract: In one embodiment, a method includes receiving a request to add a prefix to memory for a route lookup at a forwarding device, the memory comprising a plurality of pivot tiles for storing pivot entries, each of the pivot entries comprising a plurality of prefixes and a pointer to a trie index, searching at the forwarding device, a dynamic pool of the pivot tiles based on a base-width associated with the prefix, allocating at least a portion of the pivot tile to the base-width and creating a pivot entry for the prefix and other prefixes with a corresponding base-width, and dynamically updating prefixes stored on the pivot tiles based on route changes to optimize storage of prefixes on the pivot tiles. An apparatus and logic are also disclosed herein.
    Type: Application
    Filed: January 24, 2017
    Publication date: July 26, 2018
    Applicant: CISCO TECHNOLOGY, INC.
    Inventors: Nataraj Bacthu, Ayan Banerjee, Raghava Sivaramu, Ankan Ghosh
  • Patent number: 9992111
    Abstract: In one embodiment an approach is provided to efficiently program routes on line cards and fabric modules in a modular router to avoid hot spots and thus avoid undesirable packet loss. Each fabric module includes two separate processors or application specific integrated circuits (ASICs). In another embodiment, each fabric module processor is replaced by a pair of fabric module processors arranged in series with each other, and each processor is responsible for routing only, e.g., IPv4 or IPv6 traffic. The pair of fabric module processors communicates with one another via a trunk line and any packet received at either one of the pair is passed to the other of the pair before being passed back to a line card.
    Type: Grant
    Filed: January 21, 2016
    Date of Patent: June 5, 2018
    Assignee: Cisco Technology, Inc.
    Inventors: Ayan Banerjee, Raghava Sivaramu, Ambrish Mehta, Swaminathan Narayanan, Shiv Saini, Mehak Mahajan
  • Publication number: 20180026874
    Abstract: Disclosed are systems and methods for scaling Massively Scalable Data Center (MSDC) networks with a large number of end-point tunnels utilizing Equal-cost multi-path routing (ECMP). The systems and methods can use the NO-OP label operations to maintain single ECMP objects to switch a set of segment routing tunnels that share the same ECMP links. The forwarding engine can determine the use of the NO-OP label operation and update a received packet to enable the use of the single ECMP objects of the set of segment routing tunnels.
    Type: Application
    Filed: July 22, 2016
    Publication date: January 25, 2018
    Inventors: Malick Mohamed Usman, Srinivasan Ramabadran, Raghava Sivaramu, Sriram Srinivasan, Srini Ananthakrishnan
  • Publication number: 20170346721
    Abstract: Aspects of the subject technology relate to systems for arbitrating direct forwarder (“DF”) instantiation between VPC peers used to facilitating the transport of bidirectional multicast traffic over a L2/L3 network boundary. In some aspects, arbitration of DF instantiation on a given VPC peer can include determining a first set of metrics for a first VPC switch, determining a second set of metrics for a second VPC switch, and determining, at the first VPC switch, whether to instantiate a designated forwarder (DF) operation based on a comparison of the first set of metrics and the second set of metrics. Methods and machine-readable media are also provided.
    Type: Application
    Filed: July 21, 2016
    Publication date: November 30, 2017
    Inventors: Nataraj Bacthu, Raghava Sivaramu, Srinivasan Ramabadran, Terry Fangcheng Tang, Lenin Babu Dontuboyina
  • Patent number: 9742673
    Abstract: A plurality of line cards with each line card having a respective network forwarding engine and a respective outgoing interface (OIF) list and at least one fabric module communicatively coupled with each line card with each fabric module can have a respective network forwarding engine. The local OIF list can be asymmetrically programmed. The network forwarding engine of a line card can be configured to receive a multicast packet, compare a multicast address associate with the received multicast packet with entries in the local OIF list of the line card and forward the received multicast packet to at least one interface associated with the multicast address in response to the comparison resulting in a match.
    Type: Grant
    Filed: September 4, 2014
    Date of Patent: August 22, 2017
    Assignee: Cisco Technology, Inc.
    Inventors: Ayan Banerjee, Srinivasan Ramabadran, Mehak Mahajan, Raghava Sivaramu, Nataraj Bacthu, Raja Rao Tadimeti, Madhava Rao Cheethirala, Ramana Mellacheruvu
  • Patent number: 9736054
    Abstract: Methods and systems may be provided for installing a route entry associated with multicast traffic to a memory. Client devices may be notified of the route entry for advertisement by an active source device. The delivery group and delivery source may be retrieved from the information for the route entry. Multicast data trees may maintain delivery group and delivery source information for access.
    Type: Grant
    Filed: October 5, 2011
    Date of Patent: August 15, 2017
    Assignee: Cisco Technology, Inc.
    Inventors: Nataraj Bacthu, Ashok Chippa, Hasmit Grover, Raghava Sivaramu, Dino Farinacci
  • Publication number: 20170214618
    Abstract: In one embodiment an approach is provided to efficiently program routes on line cards and fabric modules in a modular router to avoid hot spots and thus avoid undesirable packet loss. Each fabric module includes two separate processors or application specific integrated circuits (ASICs). In another embodiment, each fabric module processor is replaced by a pair of fabric module processors arranged in series with each other, and each processor is responsible for routing only, e.g., IPv4 or IPv6 traffic. The pair of fabric module processors communicates with one another via a trunk line and any packet received at either one of the pair is passed to the other of the pair before being passed back to a line card.
    Type: Application
    Filed: January 21, 2016
    Publication date: July 27, 2017
    Inventors: Ayan Banerjee, Raghava Sivaramu, Ambrish Mehta, Swaminathan Narayanan, Shiv Saini, Mehak Mahajan
  • Patent number: 9634927
    Abstract: A hierarchical lookup forwarding model to induce a Layer (L2) forwarding look up in a post-routed virtual local area network (VLAN). In one example, a line card of a networking device receives a packet for routing from a first virtual local VLAN to a second VLAN. The line card determines that the packet is associated with a host route having a corresponding incomplete Layer 3 (L3) adjacency. The line card steers the packet to a fabric module of the networking device. The fabric module performs an L2 lookup on the packet and floods the packet to one or more of line cards of the networking devices. The one or more line cards flood the packet on a plurality of external ports of the networking device.
    Type: Grant
    Filed: March 13, 2015
    Date of Patent: April 25, 2017
    Assignee: Cisco Technology, Inc.
    Inventors: Hardeep Singh, Srinivasan Ramabadran, Raghava Sivaramu, Mahesh Mariappa Krishnappa
  • Patent number: 9504016
    Abstract: Techniques are provided for optimizing multicast routing in a network. At a router device, a message is sent to one or more physical devices. The message is configured to solicit a response indicating a network assignment for each of the physical devices. A response message is received from each of the physical devices. The response message comprises network assignment information for each of the physical devices. For each of the physical devices, the network assignment information is translated into a segment identifier. The segment identifier is distributed to other router devices in the network.
    Type: Grant
    Filed: February 10, 2016
    Date of Patent: November 22, 2016
    Assignee: Cisco Technology, Inc.
    Inventors: Deepak Dayama, Raghava Sivaramu, Dhananjaya Rao, Nataraj Bacthu
  • Publication number: 20160157210
    Abstract: Techniques are provided for optimizing multicast routing in a network. At a router device, a message is sent to one or more physical devices. The message is configured to solicit a response indicating a network assignment for each of the physical devices. A response message is received from each of the physical devices. The response message comprises network assignment information for each of the physical devices. For each of the physical devices, the network assignment information is translated into a segment identifier. The segment identifier is distributed to other router devices in the network.
    Type: Application
    Filed: February 10, 2016
    Publication date: June 2, 2016
    Inventors: Deepak Dayama, Raghava Sivaramu, Dhananjaya Rao, Nataraj Bacthu
  • Patent number: 9294292
    Abstract: Techniques are provided for optimizing multicast routing in a network. At a router device, a message is sent to one or more physical devices. The message is configured to solicit a response indicating a network assignment for each of the physical devices. A response message is received from each of the physical devices. The response message comprises network assignment information for each of the physical devices. For each of the physical devices, the network assignment information is translated into a segment identifier. The segment identifier is distributed to other router devices in the network.
    Type: Grant
    Filed: November 14, 2013
    Date of Patent: March 22, 2016
    Assignee: Cisco Technology, Inc.
    Inventors: Deepak Dayama, Raghava Sivaramu, Dhananjaya Rao, Nataraj Bacthu
  • Publication number: 20150131655
    Abstract: Techniques are provided for optimizing multicast routing in a network. At a router device, a message is sent to one or more physical devices. The message is configured to solicit a response indicating a network assignment for each of the physical devices. A response message is received from each of the physical devices. The response message comprises network assignment information for each of the physical devices. For each of the physical devices, the network assignment information is translated into a segment identifier.
    Type: Application
    Filed: November 14, 2013
    Publication date: May 14, 2015
    Applicant: Cisco Technology, Inc.
    Inventors: Deepak Dayama, Raghava Sivaramu, Dhananjaya Rao, Nataraj Bacthu
  • Publication number: 20150124684
    Abstract: A plurality of line cards with each line card having a respective network forwarding engine and a respective outgoing interface (OIF) list and at least one fabric module communicatively coupled with each line card with each fabric module can have a respective network forwarding engine. The local OIF list can be asymmetrically programmed. The network forwarding engine of a line card can be configured to receive a multicast packet, compare a multicast address associate with the received multicast packet with entries in the local OIF list of the line card and forward the received multicast packet to at least one interface associated with the multicast address in response to the comparison resulting in a match.
    Type: Application
    Filed: September 4, 2014
    Publication date: May 7, 2015
    Inventors: Ayan Banerjee, Srinivasan Ramabadran, Mehak Mahajan, Raghava Sivaramu, Nataraj Bacthu, Raja Rao Tadimeti, Madhava Rao Cheethirala, Ramana Mellacheruvu
  • Patent number: 8902794
    Abstract: A method is provided in one example and includes broadcasting a switching node identifier associated with a first link-state protocol enabled switching node to a plurality of link-state protocol enabled switching nodes. The plurality of link-state protocol enabled switching nodes are in communication with one another by a link-state protocol cloud. The method further includes broadcasting a priority associated with the first link-state protocol enabled switching node to the plurality of link-state protocol enabled switching nodes. The method further includes broadcasting connectivity information of the first link-state protocol enabled switching node to the plurality of link-state protocol enabled switching nodes using the link-state protocol cloud. The connectivity information includes connectivity of the first link-state protocol enabled switching node with at least one spanning tree protocol enabled switching node.
    Type: Grant
    Filed: September 27, 2012
    Date of Patent: December 2, 2014
    Assignee: Cisco Technology, Inc.
    Inventors: Varun Shah, Tissa Senevirathne, Ayan Banerjee, Ronak Desai, Raghava Sivaramu
  • Publication number: 20140269410
    Abstract: Techniques are provided for generating and updating flooding tree paths in a network. At a particular node device in a network, a first flooding tree is generated by performing a first shortest path first (SPF) operation from a first selected node device in the network to a plurality of other node devices in the network. A second flooding tree is generated by performing a second SPF operation from a second selected node device in the network to the plurality of other node devices in the network. A network topology change event is detected in either the first or second flooding tree, and a packet sequence exchange is initiated between the particular node device and another node device in the network in response to the detected network topology change. The first and second flooding trees are then updated based on information obtained during the packet sequence exchange.
    Type: Application
    Filed: March 14, 2013
    Publication date: September 18, 2014
    Applicant: CISCO TECHNOLOGY, INC.
    Inventors: Varun Shah, Ayan Banerjee, Dhananjaya Rao, Raghava Sivaramu, Abhay Roy
  • Patent number: 8837496
    Abstract: In one embodiment, a method including identifying, by a network device, a first PIM-enabled device that is communicatively coupled to the network device via a network. A determination is made that the first PIM-enabled device is designated as an IGMP querier for the network. Additionally, the method includes initiating a timer configured to expire after a predetermined period of time for the first PIM-enabled device. The method further includes, upon determining that the initiated timer has expired and that a PIM hello network message has not yet been received from the first PIM-enabled device, determining that the IGMP querier for the network is unavailable.
    Type: Grant
    Filed: May 17, 2012
    Date of Patent: September 16, 2014
    Assignee: Cisco Technology, Inc.
    Inventors: Natarja Bacthu, Siddanagouda M. Khot, Raghava Sivaramu
  • Patent number: 8755277
    Abstract: In one embodiment, a method includes receiving information on layer 2 topologies at a network device in a core network, mapping one or more Virtual Local Area Networks (VLANs) to the layer 2 topologies to provide differentiated services in said layer 2 topologies, defining multiple paths for each of the layer 2 topologies, and forwarding a packet received at the network device on one of the multiple paths. An apparatus and logic for providing differentiated services in layer 2 topologies is also disclosed.
    Type: Grant
    Filed: July 6, 2012
    Date of Patent: June 17, 2014
    Assignee: Cisco Technology, Inc.
    Inventors: Ayan Banerjee, Dino Farinacci, Raghava Sivaramu, Abhay Roy, Nair Venugopal, Sanjay Sane