Patents by Inventor Radia J. Pearlman

Radia J. Pearlman 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).

  • Determination of distance between nodes in a computer network
    Patent number: 6192404
    Abstract: A base node of a computer network sends concurrent TTL query messages using multicast to other receiving nodes of the computer network. Each of the TTL query messages has a different time-to-live (TTL) parameter value and records the TTL parameter of the TTL query message into a message body. The receiving nodes receive one or more of the TTL query messages, namely, those TTL query messages whose TTL parameter values are sufficient to allow the TTL query message to reach the receiving node. Each receiving node can determine the TTL distance to the receiving node from the base node by determining the lowest TTL parameter value of all TTL query messages which reached the receiving node. Each receiving node communicates the TTL distance by sending to the base node a TTL query response message which indicates, in the message body, the least TTL parameter value of all TTL query messages received by the receiving node.
    Type: Grant
    Filed: May 14, 1998
    Date of Patent: February 20, 2001
    Assignee: Sun Microsystems, Inc.
    Inventors: Stephen A. Hurst, Dah Ming Chiu, Stephen R. Hanna, Radia J. Pearlman
  • System for increasing the difficulty of password guessing attacks in a distributed authentication scheme employing authentication tokens
    Patent number: 5491752
    Abstract: An improved security system inhibits eavesdropping, dictionary attacks, and intrusion into stored password lists. In one implementation, the user provides a workstation with a "password", and a "token" obtained from a passive authentication token generator. The workstation calculates a "transmission code" by performing a first hashing algorithm upon the password and token. The workstation sends the transmission code to the server. Then, the server attempts to reproduce the transmission code by combining passwords from a stored list with tokens generated by a second identical passive authentication token generator just prior to receipt of the transmission code. If any password/token combination yields the transmission code, the workstation is provided with a message useful in communicating with a desired computing system; the message is encrypted with a session code calculated by applying a different hashing algorithm to the password and token.
    Type: Grant
    Filed: September 2, 1994
    Date of Patent: February 13, 1996
    Assignee: Digital Equipment Corporation, Patent Law Group
    Inventors: Charles W. Kaufman, Radia J. Pearlman, Morrie Gasser
  • System for increasing the difficulty of password guessing attacks in a distributed authentication scheme employing authentication tokens
    Patent number: 5373559
    Abstract: An improved security system inhibits eavesdropping, dictionary attacks, and intrusion into stored password lists. In one implementation, the user provides a workstation with a "password", and a "token" obtained from a passive authentication token generator. The workstation calculates a "transmission code" by performing a first hashing algorithm upon the password and token. The workstation sends the transmission code to the server. Then, the server attempts to reproduce the transmission code by combining passwords from a stored list with tokens generated by a second identical passive authentication token generator just prior to receipt of the transmission code. If any password/token combination yields the transmission code, the workstation is provided with a message useful in communicating with a desired computing system; the message is encrypted with a session code calculated by applying a different hashing algorithm to the password and token.
    Type: Grant
    Filed: March 18, 1993
    Date of Patent: December 13, 1994
    Inventors: Charles W. Kaufman, Radia J. Pearlman, Morrie Gasser