Patents by Inventor Neal D. Castagnoli

Neal D. Castagnoli 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: 6094525
    Abstract: An improved network addressing arrangement expands both the format of a network layer header and the address spaces of nodes coupled to computer networks in a manner that efficiently enhances routing among nodes of different domains of the networks. Specifically, the novel arrangement provides new elements to a conventional hierarchical network layer address and modifies existing elements, i.e., destination network and socket numbers, of that address to effectively create an improved network layer header.
    Type: Grant
    Filed: July 6, 1995
    Date of Patent: July 25, 2000
    Assignee: Novell, Inc.
    Inventors: Radia J. Perlman, Neal D. Castagnoli
  • Patent number: 5805818
    Abstract: A novel acknowledgment mechanism efficiently requests affirmation from a neighboring node coupled to a communication link of a network that the neighbor is "alive" and connected to that link. The acknowledgment mechanism comprises control information generated by a source node and generally stored in a network layer header of a data packet transmitted to the neighbor. This next-hop acknowledgement (or lack thereof) from the neighbor provides a fast and efficient indication of (lost) system connection between adjacent nodes of a network.
    Type: Grant
    Filed: September 11, 1996
    Date of Patent: September 8, 1998
    Assignee: Novell, Inc.
    Inventors: Radia J. Perlman, Neal D. Castagnoli
  • Patent number: 5781534
    Abstract: An information gathering mechanism efficiently acquires information about a path interconnecting a source node and a destination node in a computer network. The mechanism comprises a novel packet configuration for soliciting parameters pertaining to network characteristics from routers coupled to the path. This novel probe packet preferably has a flexible format so that it may be processed not only by routers configured to interpret this type of packet, but also those that are incapable of either supplying some of the parameters or, further, deciphering any of the contents of the packet.
    Type: Grant
    Filed: October 31, 1995
    Date of Patent: July 14, 1998
    Assignee: Novell, Inc.
    Inventors: Radia J. Perlman, Neal D. Castagnoli
  • Patent number: 5742820
    Abstract: A novel mechanism efficiently synchronizes the contents of databases stored on nodes of a computer network to-ensure that those contents are consistent. The mechanism comprises a database identifier generated by a node of the computer network and distributed to other receiving nodes coupled to the network. The database identifier is uniquely representative of the contents of the distributing node's database and the receiving nodes compare this unique identifier with their own generated database identifiers to determine if the identifiers, and thus their databases, are consistent and synchronized.
    Type: Grant
    Filed: July 6, 1995
    Date of Patent: April 21, 1998
    Assignee: Novell, Inc.
    Inventors: Radia J. Perlman, Neal D. Castagnoli
  • Patent number: 5596574
    Abstract: A novel synchronization mechanism synchronizes delivery of data packets over on-demand links of a computer network in a manner that efficiently utilizes those links. The mechanism comprises control information generated by a source node and stored in a network layer header of a data packet transmitted to a destination node via at least one router coupled to an on-demand link of the network. Depending upon the state of the control information the router is instructed whether to immediately dial the link to establish a connection for delivery of the packet to the destination node.
    Type: Grant
    Filed: July 6, 1995
    Date of Patent: January 21, 1997
    Assignee: Novell, Inc.
    Inventors: Radia J. Perlman, Neal D. Castagnoli