Prior art

To identify the most relevant prior art for US patent 7420952, I have consulted the patent citations listed on the Google Patents page for US7420952. The analysis focuses on a selection of these citations, prioritizing those with publication dates close to the priority date of US7420952 (October 28, 2002) and titles indicating relevance to distributed control, wireless networks, Quality of Service (QoS), and mesh networking.

The claims of US7420952 generally describe a method and system for distributed control in a wireless network where nodes (e.g., Access Points) self-configure based on parameters from an access server to optimize for latency and/or throughput, handle load balancing, and provide security and other advanced network features.

Here is an analysis of selected prior art references:

Selected Prior Art References for US7420952

1. US6424624B1

• Full Citation: US6424624B1, "Apparatus and method for controlling data flow in an ad hoc network," issued to Perlmutter et al. on July 23, 2002.
• Publication/Filing Date: Publication: July 23, 2002; Filing: June 22, 1999.
• Brief Description: This patent describes a method and apparatus for controlling data flow in an ad hoc network. It focuses on using a "traffic awareness" mechanism at intermediate nodes to detect congestion and reroute traffic. The nodes monitor traffic flow and adjust routing decisions to avoid congested paths, effectively providing a form of distributed load balancing. The system can be configured to favor certain types of traffic (e.g., real-time vs. non-real-time).
• Potential Anticipation (35 U.S.C. § 102):
  • Claims 1 (partially), 5, 6, 7, 10 (partially), 14, 15, 16: US6424624B1 describes nodes that control data flow to avoid congestion and reroute traffic, which directly relates to the load balancing aspects of US7420952. Specifically, its traffic awareness mechanism and congestion detection could anticipate elements of claims 5, 6, 7 (method for handling congestion), and claims 14, 15, 16 (node adapted for congestion handling and signal strength reduction). The concept of a node selecting a path to avoid congestion, even if not explicitly driven by an external "parameter governing a characteristic of the wireless network" from an access server, provides a distributed control mechanism for network performance.
  • Claims 2, 3, 4, 11, 12, 13: While US6424624B1 focuses on avoiding congestion, it doesn't explicitly detail the "low latency and high throughput" characteristic settings from a central access server or the specific "global throughput (GT)" metric calculation as defined in US7420952.

2. US6118776A

• Full Citation: US6118776A, "Wireless LAN system and method using self-configuring access points," issued to Bushmitch on September 12, 2000.
• Publication/Filing Date: Publication: September 12, 2000; Filing: June 18, 1999.
• Brief Description: This patent describes a wireless LAN system that uses self-configuring access points (APs). The APs automatically detect each other and establish communication paths to a wired network. The system can form a mesh-like topology where APs forward traffic for other APs, reducing the need for extensive manual configuration. It emphasizes ease of installation and automatic network formation.
• Potential Anticipation (35 U.S.C. § 102):
  • Claims 1 (partially), 8, 10 (partially), 17: The core concept of "self-configuring access points" directly anticipates the self-configuring nature of AP nodes in US7420952. While it might not detail the fine-grained control via an access server for latency/throughput as extensively as US7420952, the fundamental idea of APs establishing communication paths without manual intervention is present.
  • Claim 9: The self-contained embedded OS unit for AP nodes. While Bushmitch doesn't explicitly mention "embedded OS," the concept of APs acting as self-contained units with their own logic for self-configuration aligns with the spirit of claim 9.

3. US6665293B1

• Full Citation: US6665293B1, "Adaptive wireless communications network with a plurality of access points," issued to Perlmutter et al. on December 16, 2003.
• Publication/Filing Date: Publication: December 16, 2003; Filing: November 27, 2001.
• Brief Description: This patent describes an adaptive wireless communications network with multiple access points that can adjust their operating parameters (e.g., transmission power, channel) in response to network conditions to improve performance and coverage. It enables a more robust and efficient wireless network by dynamically adapting to changes in the radio environment and traffic load.
• Potential Anticipation (35 U.S.C. § 102):
  • Claims 1 (partially), 2, 10 (partially), 11: The adaptive nature of the network and access points adjusting parameters based on network conditions is highly relevant. The idea of "adaptive" network characteristics, even if not explicitly set by an access server for "low latency and high throughput" as a primary focus, suggests a similar underlying principle of dynamic adjustment.
  • Claims 5, 14: The adaptation to network conditions, including traffic load, could potentially anticipate aspects of load balancing and congestion avoidance.

4. US20020136209A1

• Full Citation: US20020136209A1, "Dynamic resource allocation system and method for a wireless local area network," published by O'Neill et al. on September 26, 2002.
• Publication/Filing Date: Publication: September 26, 2002; Filing: March 20, 2001.
• Brief Description: This application publication describes a system and method for dynamically allocating resources in a wireless local area network, particularly to handle Quality of Service (QoS) requirements for different types of traffic (e.g., voice, video, data). It involves monitoring network resources and reallocating them to meet the QoS demands of various applications.
• Potential Anticipation (35 U.S.C. § 102):
  • Claims 1 (partially), 2, 10 (partially), 11: The focus on dynamic resource allocation to meet QoS for different applications directly aligns with US7420952's objective of addressing "low latency requirements (for applications such as voice) and high throughput requirements (for applications involving data transfer)" through network characteristics and parameters.
  • Claims 3, 4, 12, 13: The concept of optimizing for throughput and latency, and potentially using metrics related to path quality, could find some anticipation in a system designed for dynamic resource allocation and QoS.

5. US20020085521A1

• Full Citation: US20020085521A1, "Hierarchical wireless ad hoc network for voice and data communications," published by O'Neill et al. on July 4, 2002.
• Publication/Filing Date: Publication: July 4, 2002; Filing: December 21, 2001.
• Brief Description: This application describes a hierarchical wireless ad hoc network designed to support both voice and data communications efficiently. It addresses the challenge of providing QoS for different traffic types in a dynamic environment, suggesting mechanisms for routing and resource management tailored to latency-sensitive voice and reliable data.
• Potential Anticipation (35 U.S.C. § 102):
  • Claims 1 (partially), 2, 10 (partially), 11: This reference explicitly addresses supporting both voice (low latency) and data (high throughput) in a wireless ad hoc network. This directly anticipates the core problem US7420952 aims to solve and the network characteristics it governs.
  • Claim 19 (partially): The support for efficient voice and data in a dynamic network context could implicitly involve considerations for seamless roaming and traffic management, though not explicitly detailing the "wireless switching" aspect.

6. US6760312B1

• Full Citation: US6760312B1, "Decentralized wireless network architecture," issued to Perlmutter et al. on July 6, 2004.
• Publication/Filing Date: Publication: July 6, 2004; Filing: March 18, 2002.
• Brief Description: This patent describes a decentralized wireless network architecture where nodes communicate with each other to form a resilient and scalable network. It emphasizes distributed control for routing and network management, reducing reliance on a single central point of failure. The nodes make independent decisions to optimize network performance.
• Potential Anticipation (35 U.S.C. § 102):
  • Claims 1 (partially), 10 (partially): The "decentralized wireless network architecture" and "distributed control" are fundamental aspects of US7420952's approach, where algorithms run in each AP node to determine routing. While US7420952 introduces a central access server for setting parameters, the execution of network configuration is distributed among the nodes, which aligns with the decentralized nature of US6760312B1.
  • Claims 5, 14: A decentralized architecture often inherently includes mechanisms for managing congestion and rerouting traffic in a distributed manner.

This analysis highlights that many of the core concepts in US7420952, such as self-configuration, distributed control, load balancing, and handling QoS for diverse applications, were present in various forms in prior art. The novelty of US7420952 often lies in the specific combination and detailed implementation of these features, particularly the central access server setting high-level parameters that govern the distributed decision-making of the nodes for latency/throughput tradeoffs, and the specific metrics (like GT calculation) used for parent selection.Here is an analysis of the most relevant prior art for US patent 7420952, based on the patent citations identified from the Google Patents listing for US7420952. The analysis focuses on selected references that appear most pertinent to the claims of US7420952, particularly concerning distributed control, adaptive networking, and quality of service (QoS) in wireless environments.

The claims of US7420952 generally define a method and system where wireless network nodes (e.g., Access Points) employ a control layer to receive parameters from a central access server, determine metrics (such as latency or throughput), and then independently select parent nodes to form communication paths. This system aims to achieve self-configuration, load balancing, fail-over capabilities, and application awareness for varying latency and throughput requirements.

Selected Prior Art References for US7420952

1. US6424624B1: Apparatus and method for controlling data flow in an ad hoc network

• Full Citation: US6424624B1, "Apparatus and method for controlling data flow in an ad hoc network," issued to Perlmutter et al. on July 23, 2002.
• Publication/Filing Date: Publication: July 23, 2002; Filing: June 22, 1999.
• Brief Description: This patent describes a method for managing data flow and congestion in an ad hoc wireless network. Intermediate nodes in the network monitor traffic to identify and avoid congested paths, rerouting data dynamically. This mechanism enables a distributed form of load balancing by making nodes "traffic aware" and responsive to network conditions.
• Potential Anticipation (35 U.S.C. § 102): US6424624B1 potentially anticipates elements of US7420952 related to load balancing and congestion management. Specifically, claims 5, 6, 7 (method for determining and responding to congestion, increasing connectivity cost, reducing signal strength, and forcibly disassociating clients) and claims 14, 15, 16 (wireless network node adapted to determine congestion, increase connectivity cost, reduce signal strength, and forcibly disassociate clients) are at risk. The distributed detection of congestion and adaptive routing to alleviate it, as described in Perlmutter et al., provides a similar functionality for network stability under load, even if the "parameter governing a characteristic" from a central server is not explicitly detailed.

2. US6118776A: Wireless LAN system and method using self-configuring access points

• Full Citation: US6118776A, "Wireless LAN system and method using self-configuring access points," issued to Bushmitch on September 12, 2000.
• Publication/Filing Date: Publication: September 12, 2000; Filing: June 18, 1999.
• Brief Description: This patent discloses a wireless local area network (WLAN) system where access points (APs) are designed to automatically detect each other and establish communication links to a wired backbone network without manual configuration. This self-configuration capability allows for easy deployment and the formation of mesh-like structures for extended coverage and redundancy.
• Potential Anticipation (35 U.S.C. § 102): This reference strongly anticipates the self-configuring aspects of US7420952. Claims 1 (a), (c) (establishing communication, forming a communication path, implicitly self-configuring) and claims 8, 9, 10 (c), 17 (AP nodes, control layer in embedded OS, selecting a parent node, wireless network node being an AP node) could be anticipated. The core idea of APs autonomously forming a network structure is central to both patents, though US7420952 adds the layer of central parameter control for specific network characteristics like latency/throughput.

3. US6665293B1: Adaptive wireless communications network with a plurality of access points

• Full Citation: US6665293B1, "Adaptive wireless communications network with a plurality of access points," issued to Perlmutter et al. on December 16, 2003.
• Publication/Filing Date: Publication: December 16, 2003; Filing: November 27, 2001.
• Brief Description: This patent describes an adaptive wireless network where multiple access points dynamically adjust their operational parameters, such as transmit power and channel selection, based on prevailing network conditions. This adaptation aims to optimize network performance, coverage, and resource utilization, making the network more robust and efficient in varying environments.
• Potential Anticipation (35 U.S.C. § 102): US6665293B1 potentially anticipates the adaptive nature of the network described in US7420952. Claims 1 (a)(i), (ii), (iii) (receiving parameters, determining metrics, selecting parent nodes) and claims 10 (i), (ii), (iii) (wireless network node receiving parameters, determining metrics, selecting a parent node) could be challenged. While US6665293B1 doesn't explicitly mention an "access server" setting "latency/throughput" parameters, the concept of APs adapting based on network conditions towards an optimized state aligns with the spirit of US7420952's adaptive configuration.

4. US20020136209A1: Dynamic resource allocation system and method for a wireless local area network

• Full Citation: US20020136209A1, "Dynamic resource allocation system and method for a wireless local area network," published by O'Neill et al. on September 26, 2002.
• Publication/Filing Date: Publication: September 26, 2002; Filing: March 20, 2001.
• Brief Description: This application publication details a system and method for dynamically managing resources within a wireless local area network to meet specific Quality of Service (QoS) requirements for various applications, including voice, video, and data. The system monitors network resources and reallocates them to ensure that different traffic types receive appropriate service levels.
• Potential Anticipation (35 U.S.C. § 102): This reference is highly relevant to the QoS and application-aware aspects of US7420952. Claims 1 (a)(i) (receiving a parameter governing a characteristic), 2, 3, 4 (characteristic including low latency/high throughput, metrics like hops/GT, GT calculation) and claims 10 (a)(i), 11, 12, 13 (wireless network node receiving parameters, characteristics, metrics, GT calculation) are potentially anticipated. The direct focus on dynamically meeting QoS for diverse applications by managing network resources mirrors the objectives of US7420952 in tuning the network for low latency or high throughput.

5. US20020085521A1: Hierarchical wireless ad hoc network for voice and data communications

• Full Citation: US20020085521A1, "Hierarchical wireless ad hoc network for voice and data communications," published by O'Neill et al. on July 4, 2002.
• Publication/Filing Date: Publication: July 4, 2002; Filing: December 21, 2001.
• Brief Description: This application describes a hierarchical ad hoc wireless network specifically designed to handle both voice and data communications efficiently. It addresses the challenges of providing reliable and timely delivery for latency-sensitive voice traffic while ensuring integrity for data traffic within a dynamic network structure.
• Potential Anticipation (35 U.S.C. § 102): This reference significantly anticipates the capability of US7420952 to support diverse application requirements. Claims 1 (a)(i) (receiving a parameter governing a characteristic), 2 (characteristic including low latency and high throughput), 10 (a)(i), 11 (wireless network node receiving parameters, characteristic including low latency and high throughput) are potentially anticipated. The explicit design for handling both voice and data, with their inherently different QoS needs (latency vs. throughput), directly aligns with the fundamental problem US7420952 aims to solve through its adaptive control layer.

The analysis indicates that while many individual elements of US7420952's claims are found in prior art, the specific combination, especially the role of a central access server in setting high-level characteristics that drive distributed, autonomous decisions in AP nodes for latency/throughput optimization and dynamic load balancing, presents potential distinctions.