Invalidity dossier
US 6820121
Methods systems and computer program products for processing an event based on policy rules using hashing
Current assignee: International Business Machines Corp
Added 9/21/2026, 10:22:42 AM
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 6820121 B1
Title: Methods, systems and computer program products for processing an event based on policy rules using hashing.
Assignee: International Business Machines Corporation (original assignee; per the source's own disclaimer, the listed assignee may be inaccurate because Google Patents performs no legal analysis).
Key dates: Priority/filing date 2000-08-24; granted and published 2004-11-16; status listed as expired — lifetime, adjusted expiration 2023-04-10. The source labels priority dates and legal status as assumptions, not legal conclusions. Inventors: Callis, Franks, Huynh, Nguyen, Shannon, Yang. Application US09/645,651.
Purpose and plain-language scope (per the excerpt): The invention addresses policy-rule-based network operations, e.g., quality-of-service and service-level-agreement handling. Under the IETF policy framework described, a policy rule means "if Condition then Action." Processing many such rules can be costly. The disclosed approach provides a policy rules hash table containing policy rule entries, each associated with a hash index. When an event arrives, a hash index is generated from the event's "classification" using a classification hash length (the classification has an associated length at least equal to the hash length). A matching policy rule entry is identified via that index; the system checks whether the rule's classification field length corresponds to the classification hash length, and executes the rule if so. Embodiments use a list of candidate classification hash lengths, selecting a length equal to the event's classification length, or, if absent, the largest listed length not greater than it. Rules may have multiple conditions; all must be met before execution. Identified rules may reference alternate policy rule entries, which are tried when the original rule's conditions are not met.
Source: https://patents.google.com/patent/US6820121/en
What the excerpt does not establish: It gives no complete claim set, no full description, no figures, no claim-by-claim scope, no examination history, no prior art beyond a cited IETF draft, and no independent confirmation of assignee, dates, or legal status. Details of omitted text are unknown. No litigation, ownership-transfer, validity, or prior-art analysis is offered or implied.
Generated 10/1/2026, 10:01:39 PM
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Litigation summary
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PTAB challenges
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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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