Invalidity dossier
US 7120931
System and method for generating filters based on analyzed flow data
Current assignee: Cisco Technology Inc
Added 9/21/2026, 9:35:40 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 — US7120931B1
Title: System and method for generating filters based on analyzed flow data
Patent number / application: US7120931B1; Application US09/652,454
Inventor: David Cheriton
Assignee: Cisco Technology Inc (original assignee; listed current assignee Cisco Technology Inc)
Key dates (as listed): Priority/filing date 2000-08-31; publication (grant) date 2006-10-10; adjusted expiration 2022-07-26; status "Expired - Fee Related."
Purpose. The patent addresses filtering data in high-speed computer networks, specifically the generation and refinement of filters. According to the excerpt, high-speed networks make it difficult to examine every packet or monitor every data stream without extensive hardware support, and aggregate traffic monitoring can hide offending traffic within the aggregate ("The offending or suspicious data is therefore hidden in the aggregate"). A high-rate attack or failure may also originate upstream of the affected device, compromising the link even if the device can filter the traffic.
Plain-language scope. The disclosed method generally comprises separating data into different network flows, analyzing at least one flow, detecting potentially harmful flows, and generating a filter to prevent packets corresponding to detected harmful flows from passing through the network device. A related method for propagating filters comprises generating a filter at a first network device, sending filter information to a second, upstream network device, and requesting installation of the filter there. The system uses a combination of aggregate filters and a mechanism such as a "netflow directory" of microflows to progressively refine aggregate filters and identify detailed packet characteristics involved in an attack or failure. The excerpt also mentions a computer program product and a system comprising a netflow device, a flow analyzer, and a filter generator, plus an inter-router filter propagation protocol (FPP). Classifications listed: H04L63/00, H04L63/02, H04L63/0227.
Not established by the excerpt. The excerpt is incomplete and does not provide the full claims, detailed description, or drawing contents; it does not establish claim scope, claim count, examination history, validity, ownership transfers, or any prior-art comparison.
Source: https://patents.google.com/patent/[US7120931](/patent/US7120931)/en
Generated 10/1/2026, 10:02:05 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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