Invalidity dossier
US 5369705
Multi-party secure session/conference
Current assignee: International Business Machines Corp
Added 9/23/2026, 3:50:23 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 5369705 A
Title: Multi-party secure session/conference
Patent number / application: US 5369705 A (application US 07/892,852)
Assignee: International Business Machines Corp. (original assignee; recorded assignment lists inventors Molva, Kutten, Janson, Herzberg, Bird, and Yung)
Inventors: Raymond F. Bird; Amir Herzberg; Philippe A. Janson; Shay Kutten; Refik A. Molva; Marcel M. Yung
Dates: Filing/priority date 1992-06-03; granted/publication date 1994-11-29; anticipated expiration 2012-06-03. Status listed as "Expired – Fee Related." A related Japanese priority (JP5122971A, JP2601983B2) is noted.
Purpose: To provide secure communication between users of a computer network, including a dynamic network such as a radio network, even as network topology (connectivity) changes. The text states the invention addresses limitations of existing mechanisms that are tied to two-party groups and give only one user access to the server.
Plain-language scope (per the excerpt): A group key is generated dynamically, upon demand. Each user shares an initial user key, known only to that user and the server. Users transmit alleged identity and freshness information to the server along current available paths; the server computes coded information per user, dependent on the group key, freshness information, the corresponding user key, and the alleged identity. Coded information, with attached user tags, is returned along current paths. Each user extracts the group key using its own user key; extraction succeeds only if the user is genuinely who it claims to be. The described mechanism is "insensitive to the order of communication" within the group, and uses tags so a user can identify which piece of information to use. Figures 1–9 depict a communication system, a user-key table, two-party and three-party protocols, message-flow comparisons, and initiator/responder decision trees. Descriptions use a "box/lock" analogy: a common key placed in each user's box, locked so only that user's shared key opens it.
What the excerpt does not establish: It provides no claims text, no detailed description of the omitted portions, no litigation, ownership-transfer, validity, or prior-art analysis, and no legal conclusion on status.
Generated 10/1/2026, 9:51:19 PM
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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