Patents by Inventor Vijay Rangarajan

Vijay Rangarajan 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).

  • Publication number: 20110243136
    Abstract: In one embodiment, a method includes receiving a multi-destination packet at a switch in communication with a plurality of servers through a network device, identifying a port receiving the multi-destination packet at the switch or a forwarding topology for the multi-destination packet, selecting a bit value based on the identified port or forwarding topology, inserting the bit value into a field in a virtual network tag in the multi-destination packet, and forwarding the multi-destination packet with the virtual network tag to the network device. The network device is configured to forward the multi-destination packet to one or more of the servers based on the bit value in the multi-destination packet. An apparatus for forwarding multi-destination packets is also disclosed.
    Type: Application
    Filed: March 30, 2010
    Publication date: October 6, 2011
    Applicant: CISCO TECHNOLOGY, INC.
    Inventors: Pirabhu Raman, Dinesh Dutt, Mahesh Maddury, Subbarao Arumilli, Vijay Rangarajan, Ray Kloth, Sanjay Sane
  • Patent number: 7899067
    Abstract: Methods and apparatus are disclosed for generating and using an enhanced tree bitmap data structure in determining a longest prefix match, such as in a router, packet switching system. One implementation organizes the tree bitmap to minimize the number of internal nodes that must be accessed during a lookup operation. A pointer is included in each of the trie or search nodes to the best match so far entry in the leaf or results array which allows direct access to this result without having to parse a corresponding internal node. Moreover, one implementation stores the internal node for a particular level as a first element in its child array. Additionally, one implementation uses a general purpose lookup engine that can traverse multiple tree bitmaps or other data structures simultaneously, and perform complete searches, partial searches, and resume partial searches such as after receiving additional data on which to search.
    Type: Grant
    Filed: May 31, 2002
    Date of Patent: March 1, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: Vijay Rangarajan, Dalit Sagi, William N. Eatherton
  • Patent number: 7613134
    Abstract: Methods and apparatus are disclosed for storing tree data structures among and within multiple memory channels, which may be of particular use with, but not limited to tree bitmap data structures. A subtree (or entire tree) typically includes one or more leaf arrays and multiple tree arrays. One or more leaf arrays are typically stored in a first set of memory channels of N+1 sets of memory channels, the N+1 sets of memory channels including N sets of memory channels plus the first set of memory channels. Each of N contiguous levels of the multiple tree arrays are stored in a different one of said N sets of memory channels, wherein each of the multiple tree arrays at a same level of said N contiguous levels is stored in the same memory channel set of said N sets of memory channels. A memory channel for storing a particular level is typically assigned based on one or more current occupancy levels of the memory channels.
    Type: Grant
    Filed: March 31, 2008
    Date of Patent: November 3, 2009
    Assignee: Cisco Technology, Inc.
    Inventors: Vijay Rangarajan, Shyamsundar N. Maniyar, William N. Eatherton
  • Patent number: 7508829
    Abstract: A method, performed in a network packet routing element, comprises establishing a forwarding information base (FIB) lacking a hierarchical data structure but in which one or more dependent FIB entries are associated with a parent FIB entry; establishing a plurality of strict priority queues, each having an associated priority; receiving a change to the parent FIB entry; for each of the dependent FIB entries, selecting one of the queues and enqueuing the dependent FIB entries in the selected queues for re-resolution; dequeuing the dependent FIB entries for re-resolution, according to a priority order of the queues.
    Type: Grant
    Filed: November 30, 2005
    Date of Patent: March 24, 2009
    Assignee: Cisco Technology, Inc.
    Inventors: Vijay Rangarajan, Clarence Filsfils, John Bettink
  • Publication number: 20080181139
    Abstract: Methods and apparatus are disclosed for storing tree data structures among and within multiple memory channels, which may be of particular use with, but not limited to tree bitmap data structures. A subtree (or entire tree) typically includes one or more leaf arrays and multiple tree arrays. One or more leaf arrays are typically stored in a first set of memory channels of N+1 sets of memory channels, the N+1 sets of memory channels including N sets of memory channels plus the first set of memory channels. Each of N contiguous levels of the multiple tree arrays are stored in a different one of said N sets of memory channels, wherein each of the multiple tree arrays at a same level of said N contiguous levels is stored in the same memory channel set of said N sets of memory channels. A memory channel for storing a particular level is typically assigned based on one or more current occupancy levels of the memory channels.
    Type: Application
    Filed: March 31, 2008
    Publication date: July 31, 2008
    Applicant: Cisco Technology, Inc., a corporation of California
    Inventors: VIJAY RANGARAJAN, SHYAMSUNDAR N. MANIYAR, WILLIAM N. EATHERTON
  • Patent number: 7352739
    Abstract: Tree data structures are stored among and within multiple memory channels, which may be of particular use with, but not limited to tree bitmap data structures. A subtree (or entire tree) typically includes one or more leaf arrays and multiple tree arrays. One or more leaf arrays are typically stored in a first set of memory channels of N+1 sets of memory channels, the N+1 sets of memory channels including N sets of memory channels plus the first set of memory channels. Paths of the multiple tree arrays are typically stored in said N memory channels, wherein each tree array of the multiple tree arrays associated with one of said paths is stored in a different one of said N sets of memory channels.
    Type: Grant
    Filed: January 31, 2003
    Date of Patent: April 1, 2008
    Assignee: Cisco Technology, Inc.
    Inventors: Vijay Rangarajan, Shyamsundar N. Maniyar, William N. Eatherton
  • Patent number: 7349415
    Abstract: Methods and apparatus are disclosed for generating and using an enhanced tree bitmap data structure in determining a longest prefix match, such as in a router, packet switching system. One implementation organizes the tree bitmap to minimize the number of internal nodes that must be accessed during a lookup operation. A pointer is included in each of the trie or search nodes to the best match so far entry in the leaf or results array which allows direct access to this result without having to parse a corresponding internal node. Moreover, one implementation stores the internal node for a particular level as a first element in its child array. Additionally, one implementation uses a general purpose lookup engine that can traverse multiple tree bitmaps or other data structures simultaneously, and perform complete searches, partial searches, and resume partial searches such as after receiving additional data on which to search.
    Type: Grant
    Filed: October 23, 2002
    Date of Patent: March 25, 2008
    Assignee: Cisco Technology, Inc.
    Inventors: Vijay Rangarajan, Dalit Sagi, William N. Eatherton
  • Publication number: 20070121524
    Abstract: A method, performed in a network packet routing element, comprising establishing a forwarding information base (FIB) lacking a hierarchical data structure but wherein one or more dependent FIB entries are associated with a parent FIB entry; establishing a plurality of strict priority queues, wherein each of the queues has an associated priority; receiving a change to the parent FIB entry; for each of the dependent FIB entries, selecting one of the queues and enqueuing the dependent FIB entries in the selected queues for re-resolution; dequeuing the dependent FIB entries for re-resolution, according to a priority order of the queues.
    Type: Application
    Filed: November 30, 2005
    Publication date: May 31, 2007
    Inventors: Vijay Rangarajan, Clarence Filsfils, John Bettink
  • Publication number: 20050157712
    Abstract: Methods and apparatus are disclosed for generating and using an enhanced tree bitmap data structure in determining a longest prefix match, such as in a router, packet switching system. One implementation organizes the tree bitmap to minimize the number of internal nodes that must be accessed during a lookup operation. A pointer is included in each of the trie or search nodes to the best match so far entry in the leaf or results array which allows direct access to this result without having to parse a corresponding internal node. Moreover, one implementation stores the internal node for a particular level as a first element in its child array. Additionally, one implementation uses a general purpose lookup engine that can traverse multiple tree bitmaps or other data structures simultaneously, and perform complete searches, partial searches, and resume partial searches such as after receiving additional data on which to search.
    Type: Application
    Filed: October 23, 2002
    Publication date: July 21, 2005
    Inventors: Vijay Rangarajan, Dalit Sagi, William Eatherton
  • Publication number: 20040008634
    Abstract: Methods and apparatus are disclosed for generating and using an enhanced tree bitmap data structure in determining a longest prefix match, such as in a router, packet switching system. One implementation organizes the tree bitmap to minimize the number of internal nodes that must be accessed during a lookup operation. A pointer is included in each of the trie or search nodes to the best match so far entry in the leaf or results array which allows direct access to this result without having to parse a corresponding internal node. Moreover, one implementation stores the internal node for a particular level as a first element in its child array. Additionally, one implementation uses a general purpose lookup engine that can traverse multiple tree bitmaps or other data structures simultaneously, and perform complete searches, partial searches, and resume partial searches such as after receiving additional data on which to search.
    Type: Application
    Filed: May 31, 2002
    Publication date: January 15, 2004
    Inventors: Vijay Rangarajan, Dalit Sagi, William N. Eatherton