Invalidity dossier
US 6643260
Method and apparatus for implementing a quality of service policy in a data communications network
Current assignee: Cisco Technology Inc
Added 9/23/2026, 11:48:42 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: US6643260B1
Title: Method and apparatus for implementing a quality of service policy in a data communications network
Patent number: US6643260B1
Application number: US09/213,105
Inventors: Raymond J. Kloth; Thomas J. Edsall; Michael Fine; Dinesh G. Dutt
Assignee: Cisco Technology, Inc. (original assignee; assignment recorded 1999-03-05)
Priority/filing date: 1998-12-18
Grant/publication date: 2003-11-04
Legal status (as listed): Expired – Lifetime; anticipated expiration 2018-12-18
Source: https://patents.google.com/patent/[US6643260](/patent/US6643260)/en
Purpose (from the text): The invention relates to implementing a quality of service (QoS) policy in a data communications network, so as to prioritize network traffic into a plurality of service levels and provide preferential treatment of different classes of data traffic. It addresses the problem that network devices face in identifying and grouping transmissions to be given preferential treatment or restricted. Such groupings must be consistently applied at the rate traffic is passing, without introducing additional delays or bottlenecks. The text notes routers previously kept packet counts and rate limited packets in software, but that router software has not scaled to processing millions of packets per second while also providing basic routing functions.
Plain-language scope (as far as the excerpt shows): The patent concerns classifying packet traffic for QoS. It describes packet formats used for identifying traffic, including Layer 2 encapsulation with MAC destination/source addresses, data, and CRC; the IEEE 802.1q tag containing three priority bits (a "Class of Service" or CoS field); and the IP packet's ToS/Differentiated Service field, protocol type, source and destination IP addresses, and Layer 4 source/destination ports. Groupings may be by protocol type, destination IP address, source IP address, address pair, or source/destination port. The claims and full written description are not included above.
What the excerpt does not establish: It does not include the claims, detailed embodiments (e.g., CAM/codepoint operation), the full written description, or Figures 1A–1C content. It does not establish validity, enforceability, litigation, or ownership transfers beyond the recorded assignment.
Generated 10/1/2026, 9:32:17 PM
Cases on file (0)
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Litigation summary
Past and pending lawsuits — plaintiffs, defendants, jurisdictions, outcomes, and notable rulings.
Proceedings on file (0)
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No PTAB proceedings on file. This patent has not been challenged via IPR, PGR, or CBM. The absence is itself a signal — well-asserted patents eventually attract IPRs. The LLM analysis below may surface filings the ODP feed hasn’t indexed yet.
PTAB challenges
AIA trial proceedings at the USPTO Patent Trial and Appeal Board — IPR, PGR, and CBM. Petitioners, judge panels, claim-level invalidation outcomes from Final Written Decisions, and Federal Circuit appeals. The single most important defensive datapoint after litigation history.
Assignment history
Inventors, original assignee, and the chain of ownership recorded with the USPTO — including the correspondent attorney who recorded each assignment, since shell-LLC chains often share one repeat-player attorney even when the entity names look unrelated. Surfaces NPE / patent-troll patterns: shell-entity transfers, known asserters in the chain, repeat correspondent fingerprints, pre-litigation assignments, and bankruptcy fire-sales.
Prior art
Earlier patents, publications, and products that may anticipate or render the claims unpatentable.
Obviousness
Combinations of prior art that suggest the claimed invention would have been obvious under 35 U.S.C. § 103.
Extensions
Patent term adjustments, term extensions, continuations, divisionals, family members, and expiration dates.
Derivative works
Defensive disclosure: derivative variations of each claim designed to render future incremental improvements obvious or non-novel.