US 7054264

US patent 7054264, titled "Interconnect and gateway protection in bidirectional ring networks," was invented by Gal Mor. The patent was filed on July 24, 2001, and issued on May 30, 2006. Its original assignee was Orckit Corrigent Ltd., and the current assignee is Quicker Connections LLC.

Abstract:
The patent describes a communication device designed to interconnect a first network, which is at least a bidirectional ring network, with a second network. This device includes two interconnect modules. Each module is configured to receive outgoing data from the first network at a data rate not significantly exceeding the maximum rate for one direction of the ring and to convey this data to the second network. Similarly, it receives incoming data from the second network and conveys it to the first network. In the event of a fault in one of these modules, the other module receives a fault indication and is reconfigured to handle substantially all outgoing data traffic, regardless of its original transmission direction (clockwise or counterclockwise) on the first network, and then conveys it to the second network.

Plain-Language Overview of Independent Claims:

• Independent Claim 1 (Communication Device):
  This claim describes a device that connects two networks, where at least the first network is a bidirectional ring network (meaning traffic flows both clockwise and counterclockwise, each with a maximum data rate). The device features two interconnected modules. In normal operation, the first module only handles outgoing traffic moving clockwise on the first network, while the second module only handles outgoing traffic moving counterclockwise. Crucially, each module is designed so its interface bandwidth for receiving outgoing traffic doesn't exceed the maximum rate of a single directional ring. If one module fails, the other module detects this and takes over, receiving virtually all outgoing traffic from the first network (from both directions) and sending it to the second network.

• Independent Claim 9 (Communication Device with MAC Addresses):
  Similar to Claim 1, this claim also describes a communication device for interconnecting two networks, with the first being a bidirectional ring network having a predetermined maximum data rate per direction. A key feature here is that both interconnect modules are configured with Media Access Control (MAC) addresses for both themselves and the other module. During normal operation, each module only processes outgoing data destined for its own MAC address, at a data rate not exceeding the predetermined maximum for one direction. If one module fails, the working module receives an alert and begins accepting outgoing data destined for both MAC addresses (its own and the failed module's) to convey to the second network.

• Independent Claim 13 (Communication Method):
  This claim outlines a method for communication between two networks, where at least the first is a bidirectional ring network with traffic in both directions, each at a maximum data rate. The method involves connecting the networks using two interconnect modules. When both modules are functional, the first module handles outgoing traffic from the first network exclusively from the clockwise direction, and the second module handles it exclusively from the counterclockwise direction. Each module is set up to receive this traffic at a rate not exceeding the maximum data rate of a single direction. Should one module fail, the other module is reconfigured to receive substantially all outgoing traffic from the first network to transmit to the second network.

• Independent Claim 21 (Communication Method with MAC Addresses):
  This method claim details a communication process between two networks, with at least the first being a bidirectional ring network with specified maximum data rates for each direction. It involves coupling the networks via two interconnect modules. The method includes assigning unique MAC addresses to each module and configuring both modules with the MAC addresses of both. In normal operation, each module receives outgoing data from the first network destined only for its own MAC address (at a rate not exceeding the maximum for one direction) and conveys it to the second network. If a fault occurs in one module, the other module is then configured to receive all outgoing traffic destined for both MAC addresses (its own and the failed module's) and convey it to the second network.

CAFC 2026 Dockets:
As of July 29, 2026, there is no authoritative information available from the search regarding specific dockets for US patent 7054264 in the U.S. Court of Appeals for the Federal Circuit (CAFC) for the year 2026. General information on accessing CAFC case filings and records is available. The patent's legal status indicates it expired on April 27, 2024. However, it is noted that the patent family has ongoing litigation in the Texas Eastern District Court (case 2:24-cv-01074), which was filed in 2024.

As a patent attorney, I have investigated litigation involving US Patent 7054264.

Based on available information, US Patent 7054264 is currently involved in litigation in the Eastern District of Texas:

• Plaintiff(s): Quicker Connections LLC
• Defendant(s): Not specified in the provided information, but the case is filed in the Eastern District of Texas.
• Jurisdiction: Texas Eastern District Court
• Case Number: 2:24-cv-01074
• Filing Date: Not explicitly stated, but the case number "2:24-cv-01074" suggests a filing in 2024.
• Outcome/Current Status: The case is currently active, as indicated by its listing on the Unified Patents portal as "litigation" and "critical".

It's worth noting that Unified Patents is an organization focused on deterring frivolous patent litigation, particularly from Non-Practicing Entities (NPEs), often referred to as "patent trolls." They achieve this by challenging the validity of NPE patents and providing information on patent litigation.

Proceedings overview

There are no AIA trial proceedings on file for US patent 7054264 as of the most recent ingest from the USPTO ODP API. Web search also did not surface any older or recently-filed proceedings. Therefore, there is no PTAB activity on file for this patent.

Strategic summary

As there are no AIA trial proceedings on file for US7054264, all claims (1-24) of the patent remain untested by the PTAB. There is no estoppel landscape to consider under § 315(e)(2) since no petitions have been instituted. There are no patterns of PTAB filings by petitioners or appeals by the patent owner to discern.

Recommended next steps

If you are a defendant facing assertion of US7054264, the absence of PTAB activity indicates that the patent has not yet been subjected to an inter partes review, post-grant review, or covered business method review. This means that all claims are currently presumed valid as granted. If you are considering challenging the patent, you would have the full range of prior art grounds (e.g., anticipation under § 102 or obviousness under § 103) available to you, subject to the statutory deadlines for filing such petitions. The absence of PTAB activity could also signal that the patent has not been extensively asserted, or that previous assertions were settled before PTAB challenges were initiated.

Inventors

• Gal Mor. At the time of filing, Gal Mor was an inventor for Corrigent Systems Ltd., as evidenced by the initial assignment of rights to the company.

Original assignee

The original assignee, Corrigent Systems Ltd., was a developer of high-speed packet transport network solutions, particularly focusing on Resilient Packet Ring (RPR) technology for metropolitan area networks. The patent's subject matter, "Interconnect and gateway protection in bidirectional ring networks," is directly aligned with their core business. It is highly likely they shipped products embodying the claims. Corrigent Systems Ltd. was later acquired by Orckit Communications Ltd. in 2006, after which it operated as Orckit-Corrigent Ltd. The patent expired on April 27, 2024.

Assignment timeline

• 2001-07-15 (executed) / recorded 2001-07-24 — Reel 012017/0934
  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST
  • Assignor: MOR, GAL
  • Assignee: CORRIGENT SYSTEMS LTD.
  • Correspondent: GIDEON BEN ZVI, ADV. 35 HABARZEL ST., RAMAT HACHAYAL TEL-AVIV, 69710 ISRAEL. This correspondent also appears later on a release.
  • Context: Inventor assigned patent rights to his employer as part of standard employment.
• 2009-09-06 (executed) / recorded 2014-04-01 — Reel 032579/0201
  • Conveyance: CHANGE OF NAME
  • Assignor: CORRIGENT SYSTEMS LTD.
  • Assignee: ORCKIT-CORRIGENT LTD.
  • Correspondent: ORCKIT COMMUNICATION LTD. 12 HARAKMON ST. NORTH IND. ZONE LOD, ISRAEL.
  • Context: Original assignee underwent a corporate name change following an acquisition.
• 2013-03-18 (executed) / recorded 2013-03-18 — Reel 030033/0774
  • Conveyance: SECURITY AGREEMENT
  • Assignor: ORCKIT-CORRIGENT LTD.
  • Assignee: HUDSON BAY IP OPPORTUNITIES MASTER FUND, LP
  • Correspondent: KRAMER LEVIN NAFTALIS & FRANKEL LLP 1177 AVENUE OF THE AMERICAS NEW YORK, NY 10036.
  • Context: Operating company secured financing using the patent as collateral.
• 2013-07-23 (executed) / recorded 2013-07-26 — Reel 030887/0983
  • Conveyance: RELEASE BY SECURED PARTY
  • Assignor: HUDSON BAY IP OPPORTUNITIES MASTER FUND LP
  • Assignee: ORCKIT-CORRIGENT LTD.
  • Correspondent: ORCKIT-CORRIGENT LTD. C/O ADV. GIDEON BEN ZVI 35 HABARZEL ST. RAMAT HACHAYAL TEL-AVIV 69710 ISRAEL. Gideon Ben Zvi was also the correspondent for the initial inventor assignment.
  • Context: Lender released the security interest in the patent, returning full rights to the operating company.
• 2016-04-25 (executed) / recorded 2016-05-10 — Reel 038529/0087
  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST
  • Assignor: CORRIGENT SYSTEMS LTD., ORCKIT COMMUNICATION LTD., ORCKIT-CORRIGENT LTD.
  • Assignee: ORCKIT IP, LLC
  • Correspondent: ROTHWELL, FIGG, ERNST & MANBECK, P.C. 607 14TH STREET NW SUITE 800 WASHINGTON, DC 20005.
  • Context: Operating company (Orckit-Corrigent Ltd. and related entities) transferred patent to an IP holding company, signaling a potential shift towards licensing.
• 2022-08-10 (executed) / recorded 2025-04-26 — Reel 070953/0085
  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST
  • Assignor: ORCKIT IP, LLC.
  • Assignee: SUCA LTD.
  • Correspondent: SCHULMAN & TAJGAR INC. 370 WEST 35TH STREET SUITE 2B NEW YORK, NEW YORK 10001. This correspondent also appears immediately after this entry in the chain.
  • Context: IP holding company transferred patent to another entity, part of a series of rapid transfers.
• 2022-10-25 (executed) / recorded 2025-05-12 — Reel 071087/0641
  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST
  • Assignor: SUCA LTD.
  • Assignee: QUICKER CONNECTIONS LLC
  • Correspondent: SCHULMAN & TAJGAR INC. 370 WEST 35TH STREET SUITE 2B NEW YORK, NEW YORK 10001. This correspondent appeared immediately prior in the chain.
  • Context: Another transfer between IP-focused entities, completing a short series of transfers.
• 2024-10-08 (executed) / recorded 2024-10-23 — Reel 069230/0593
  • Conveyance: PATENT SECURITY AGREEMENT
  • Assignor: QUICKER CONNECTIONS LLC
  • Assignee: IP LITFIN US 2024 LLC
  • Correspondent: PARAGON LAW GROUP PLLC 106 W. 6TH STREET SUITE 900 AUSTIN, TEXAS 78701.
  • Context: Current owner secured financing using the patent as collateral, occurring after the patent's expiration.

Timeline diagram

timeline
    title Ownership of US 7054264
    2001 : Inventor assigned to Corrigent Systems
    2006 : Patent Issued
    2009 : Corrigent changed name
    2013 : Security agreement with Hudson Bay
         : Release by Hudson Bay
    2016 : Assigned to Orckit IP LLC
    2022 : Assigned to Suca Ltd
         : Assigned to Quicker Connections
    2024 : Patent expired
         : Security agreement IP Litfin

NPE / troll-pattern signals

1. Shell-entity transfer: Present
   • The transfer from Orckit-Corrigent Ltd. (an operating company) to ORCKIT IP, LLC, evidenced by the "IP, LLC" suffix, suggests a move to a licensing-focused entity (executed 2016-04-25, Reel 038529/0087). Subsequent transfers to SUCA LTD and QUICKER CONNECTIONS LLC, both LLCs, further support this pattern (executed 2022-08-10, Reel 070953/0085 and executed 2022-10-25, Reel 071087/0641).
2. Known asserter in the chain: Present
   • Quicker Connections LLC, the current assignee, is identified by Google Patents as having litigation activity related to this patent family, specifically case 2:24-cv-01074 in the Texas Eastern District Court, which indicates it is an asserting entity.
3. Repeat correspondent across the chain: Present
   • The firm SCHULMAN & TAJGAR INC. is listed as the correspondent for two consecutive assignments: from ORCKIT IP, LLC to SUCA LTD (Reel 070953/0085) and from SUCA LTD to QUICKER CONNECTIONS LLC (Reel 071087/0641). This pattern suggests a common legal representative for a series of transfers between IP-focused entities.
4. Cascading transfers: Present
   • There were two successive assignments in late 2022, from ORCKIT IP, LLC to SUCA LTD (executed 2022-08-10) and then to QUICKER CONNECTIONS LLC (executed 2022-10-25). Both transfers were handled by the same correspondent firm, indicating a rapid transfer through chained LLCs.
5. Pre-litigation transfer: Not present
   • The assignment to Quicker Connections LLC was executed on 2022-10-25 (Reel 071087/0641). The litigation referenced on Google Patents has a case number 2:24-cv-01074, implying a 2024 filing. This timeframe is more than six months after the assignment, so it does not strictly meet the criteria for a pre-litigation transfer.
6. Bankruptcy fire-sale: Not present
   • There is no evidence from the assignment records or Google Patents that the original assignee underwent bankruptcy proceedings.
7. Privateering: Unclear
   • While the patent moved from an operating company to an IP entity, there is no explicit information in the provided records (e.g., SEC filings) to confirm a privateering arrangement where the original operating company is leveraging an NPE to assert patents against competitors.
8. Defensive aggregator (anti-NPE): Not present
   • The patent is not currently assigned to any known defensive aggregators such as RPX, AST, LOT Network, Unified Patents, or Open Invention Network. Instead, the current assignee is involved in litigation.

Verdict

NPE — high confidence

This verdict is supported by multiple strong signals. The patent was transferred from an operating company to an IP-centric LLC (Orckit IP, LLC) in 2016 (Reel 038529/0087). This was followed by cascading transfers to other LLCs (Suca LTD, Quicker Connections LLC) in 2022 (Reel 070953/0085, Reel 071087/0641), with a repeat correspondent (Schulman & Tajgar Inc.) handling these subsequent assignments. Crucially, the current assignee, Quicker Connections LLC, is actively asserting the patent in litigation, as indicated by a case filed in the Texas Eastern District Court.

Verify assignments at: https://assignmentcenter.uspto.gov/#!/assignment-result/[7054264](/patent/7054264)

The search results confirm the availability of USPTO Public Search tools. I can use these to find details of the cited patents. I'll proceed with extracting the details for the most relevant prior art references as planned. I will synthesize the description from the patent abstracts and relevant sections in the provided text.

Here are the most relevant prior art references for US patent 7054264, focusing on those cited by the examiner:

Most Relevant Prior Art for US Patent 7054264

The analysis focuses on patents cited by the examiner that predate the July 24, 2001 filing date of US7054264.

1. US6952397B2: Communication in a bidirectional ring network with single-direction receiving

• Full Citation: US6952397B2, "Communication in a bidirectional ring network with single-direction receiving"
• Publication/Filing Date:
  • Priority Date: 2001-06-07
  • Filing Date: 2001-06-07
  • Publication Date: 2005-10-04
• Brief Description: This patent describes a method and apparatus for communicating in a bidirectional ring network where each node, when transmitting data to a destination node, sends the data in both clockwise and counterclockwise directions around the ring. Crucially, each node is configured to receive data only from one of the two directions (either clockwise or counterclockwise) for any given packet, thereby enabling spatial reuse of bandwidth. Upon detection of a fault in the network, the receiving direction for packets is reconfigured at one or more nodes to restore communication. This approach maintains fast protection against faults while efficiently utilizing network bandwidth.
• Potential Anticipation under 35 U.S.C. § 102: US6952397B2 appears to potentially anticipate several claims of US7054264, particularly those related to the core mechanism of load sharing and fault recovery:
  • Claim 1: The concept of a bidirectional ring network with traffic in both directions, the use of two modules (analogous to specialized nodes or components within a node), and critically, the configuration where each module (or node in US6952397B2) normally receives traffic from only one direction, and then reconfigures to receive all traffic upon a fault, is directly taught. The bandwidth efficiency achieved by sizing modules to handle a single directional flow in normal operation and relying on network-level traffic redirection (wrapping/steering, as mentioned in US7054264's description) during a fault aligns with the description of US6952397B2.
  • Claim 2 & 3: These claims relate to the ability of modules to transmit incoming data in both directions and the other module receiving both clockwise and counterclockwise outgoing data upon a fault, which are inherent in the fault recovery and bidirectional nature described in US6952397B2.
  • Claim 5: This claim concerns configuring modules with MAC addresses for both modules and switching to receive traffic destined for both MAC addresses upon a fault. US6952397B2 discusses configuring access units with MAC addresses (e.g., protected/unprotected MAC addresses) and updating forwarding databases upon a fault, which strongly implies a similar MAC address management for fault recovery.
  • Claim 9, 13, 14, 15, 16, 21: These method and device claims further detail the communication method, including load sharing by direction and MAC address reassignment during fault, which are substantially present in the teachings of US6952397B2.
  • Relationship to US7054264: It is important to note that US6952397B2 shares the same original assignee (Corrigent Systems Ltd.) as US7054264 and has an earlier priority/filing date. The title, "Communication in a bidirectional ring network with single-direction receiving," directly points to a core concept also central to US7054264.

2. US6820210B1: System and method for fault recovery for a two line bi-directional ring network

• Full Citation: US6820210B1, "System and method for fault recovery for a two line bi-directional ring network"
• Publication/Filing Date:
  • Priority Date: 1998-04-27
  • Filing Date: 1998-04-27
  • Publication Date: 2004-11-16
• Brief Description: This patent describes a system and method for rapidly recovering from faults (e.g., link or node failures) in a two-line bidirectional ring network, such as a Resilient Packet Ring (RPR). The invention focuses on detecting faults and dynamically re-routing traffic around the fault using mechanisms like "wrapping" or "steering" to ensure minimal service interruption. It utilizes source and destination addresses and control messages to manage the fault recovery process.
• Potential Anticipation under 35 U.S.C. § 102: US6820210B1 is highly relevant for its detailed discussion of fault recovery mechanisms in bidirectional ring networks, particularly RPR, which is a technology mentioned in US7054264.
  • Claim 1 (Preamble and fault recovery aspects): The patent describes a bidirectional ring network with fault recovery. The core idea of detecting a fault and re-routing traffic (via wrapping or steering) so that another part of the network handles the traffic is clearly disclosed.
  • Claim 4 & 17: These claims specifically mention "wrapping the traffic between the clockwise and counterclockwise directions, away from the module in which the fault occurred." This wrapping mechanism is a central feature of the fault recovery system in US6820210B1.
  • Claim 13 & 16: These method claims involve reconfiguring a module to receive substantially all outgoing traffic and receiving traffic in both directions upon a fault, which aligns with the dynamic re-routing and recovery principles taught.
  • Distinction from US7054264: While US6820210B1 provides strong art for RPR fault recovery and traffic redirection, it does not explicitly detail the specific architecture of "first and second interconnect modules" acting as a gateway between two distinct networks with the explicit load-sharing of incoming traffic by direction in normal operation, nor the precise bandwidth limitation for each module relative to the maximum data rate of a single ring direction, as claimed in US7054264.

3. US5307353A: Fault recovery system of a ring network

• Full Citation: US5307353A, "Fault recovery system of a ring network" (Also reissued as USRE37401E1)
• Publication/Filing Date:
  • Priority Date: 1990-05-09
  • Filing Date: 1990-05-09
  • Publication Date: 1994-04-26
• Brief Description: This patent discloses a fault recovery system for a ring network utilizing two transmission lines for data transfer in opposite directions (clockwise and counterclockwise). The system comprises ring stations (nodes) connected to both lines. Upon detecting a fault, the stations perform a loop-back (wrapping) operation to bypass the faulty segment, ensuring continuous communication. The system describes transmitting data over both paths and receiving over one in normal operation, then switching to the other path upon fault.
• Potential Anticipation under 35 U.S.C. § 102: US5307353A lays fundamental groundwork for fault-tolerant bidirectional ring networks.
  • Claim 1 (Preamble and general fault recovery): The patent broadly covers a ring network with bidirectional traffic and a fault recovery mechanism where stations detect faults and reroute traffic (e.g., via loop-back/wrapping) to maintain communication. The concept of receiving data over one path in normal operation and switching to another upon fault is also present.
  • Claim 4 & 17: The wrapping/loop-back mechanism for fault recovery, as described in US7054264, is a central feature of US5307353A.
  • Distinction from US7054264: While foundational, US5307353A focuses more on maintaining connectivity within a single ring and less on the specific architecture of two interconnect modules serving as a gateway between two different networks with the defined load-sharing of outgoing traffic by direction and the associated per-module bandwidth limitations as claimed in US7054264. It predates modern packet ring protocols like RPR which US7054264 explicitly references.

The obviousness of US patent 7054264 under 35 U.S.C. § 103 can be established by combining known prior art references, as a person having ordinary skill in the art (PHOSITA) would have been motivated to make such combinations. The critical date for prior art assessment is the patent's priority date of July 24, 2001.

The core of US7054264 describes a communication device and method for interconnecting two networks, where at least the first network is a bidirectional ring network. This device features first and second interconnect modules that, during normal operation, share the load of outgoing data traffic by having one module configured to receive traffic only from the clockwise direction and the other only from the counterclockwise direction. Upon a fault in one module, the other module is reconfigured to receive substantially all outgoing data traffic. Crucially, due to traffic redirection (e.g., wrapping or steering) inherent in bidirectional ring protocols, each module's interface bandwidth is not substantially greater than the maximum data rate of one ring direction, even during failover. The patent also describes configuring modules with each other's Media Access Control (MAC) addresses for rapid fault recovery.

A PHOSITA in 2001 would have possessed a strong understanding of:

• Bidirectional ring networks and their associated protocols (e.g., Resilient Packet Rings (RPR) and Spatial Reuse Protocol (SRP)), including their inherent fault protection mechanisms like traffic wrapping or steering.
• The general principles of interconnecting different network topologies using gateway nodes.
• Various redundancy and load-sharing techniques for enhancing the reliability and efficiency of network devices.
• Media Access Control (MAC) layer operations and the use of MAC addresses for packet routing and rapid failover in redundant systems.

Obviousness Combination 1: Directional Load Sharing and Bandwidth-Efficient Failover in a Dual-Module Gateway (Addressing Claims 1, 3, 13, 16)

References:

1. US6952397B2 (Corrigent Systems Ltd.) - "Communication in a bidirectional ring network with single-direction receiving" (Priority Date: June 7, 2001). This patent teaches a method for nodes on a bidirectional ring network to receive data packets primarily from one direction (e.g., clockwise or counterclockwise) at any given time, and to switch to receiving packets from the other direction upon detecting a fault in the primary direction. [cite: US6952397B2]
2. US5218604A (Bell Communications Research, Inc.) - "Dual-hubbed arrangement to provide a protected ring interconnection" (Priority Date: August 31, 1990). This reference discloses redundant arrangements for interconnecting ring networks, indicating the known practice of using multiple components for reliability at network interconnect points. [cite: US5218604A]
3. Jogalekar et al., "IP Over Resilient Packet Rings" (Internet Draft draft-jogalekar-iporpr-00, November 2000), Tsiang et al., "Spatial Reuse Protocol (SRP)" (RFC 2892), and IEEE 802.17 (RPR protocol). These non-patent references, along with the patent's own background section, confirm that bidirectional ring networks and their inherent fault protection mechanisms (such as wrapping or steering traffic around a fault) were well-known in the art. [cite: Jogalekar et al., Tsiang et al., US7054264 Description, 0012]

Motivation to Combine and Explanation of Obviousness:
A PHOSITA, tasked with designing a fault-tolerant and bandwidth-efficient gateway for a bidirectional ring network, would recognize the limitations of traditional active/standby redundancy where the backup unit sits idle or requires significantly over-provisioned bandwidth. The patent itself highlights this problem. [cite: US7054264 Description, 0005].

1. Redundant Interconnects: Knowing the need for robust interconnects, a PHOSITA would naturally consider a redundant gateway architecture, such as a dual-module setup, drawing on prior art like US5218604A which describes dual-hubbed protected ring interconnections. [cite: US5218604A]
2. Leveraging Bidirectional Nature: Observing the inherent two-directional traffic flow (clockwise and counterclockwise) in modern bidirectional ring networks (e.g., RPR as described by Jogalekar and Tsiang), the PHOSITA would be motivated to efficiently utilize both redundant gateway modules during normal operation rather than having one remain idle. [cite: Jogalekar et al., Tsiang et al.]
3. Directional Load Sharing: The concept of "single-direction receiving" taught by US6952397B2, where a node can be configured to receive traffic predominantly from one direction, provides a clear teaching for how to achieve such load balancing. [cite: US6952397B2 Abstract, US6952397B2 Column 5 Lines 5-10] It would be obvious to apply this principle to a dual-module gateway: configure one module to receive outgoing traffic solely from the clockwise direction of the ring, and the other module to receive outgoing traffic solely from the counterclockwise direction. This effectively shares the normal operational load.
4. Failover Mechanism: Furthermore, in a redundant system, it is a well-understood principle that if one component fails (detected by standard mutual communication), the surviving component takes over the entire load. Therefore, it would be obvious for the operational gateway module to assume responsibility for receiving outgoing traffic from both ring directions upon a fault in its peer.
5. Bandwidth Efficiency: The crucial "bandwidth not substantially greater than the predetermined maximum" feature is an inherent outcome of combining the above elements with the known behavior of bidirectional ring protocols. As explicitly stated in US7054264, these protocols (RPR/SRP) are designed to redirect traffic (wrap or steer) around a fault on the ring itself. [cite: US7054264 Description, 0012, 0043] Consequently, if one gateway module fails, the ring's protection mechanism would channel all traffic destined for the gateway to the single active module through one effective path on the ring. This means the surviving module would only need to process a bandwidth equivalent to one ring direction's maximum data rate, thereby achieving the claimed bandwidth efficiency without requiring over-provisioning.

Thus, the combination of known bidirectional ring properties (Jogalekar, Tsiang, IEEE 802.17), redundant interconnect design (US5218604A), and the specific teaching of single-direction receiving and failover (US6952397B2) would render claims 1, 3, 13, and 16 obvious to a PHOSITA.

Obviousness Combination 2: MAC Address-Based Rapid Failover (Addressing Claims 5, 9, 15, 21)

References:

1. Combination 1 above (a dual-module gateway providing directional load sharing and bandwidth-efficient failover in a bidirectional ring network).
2. Tsiang et al., "Spatial Reuse Protocol (SRP)" (RFC 2892). This document details Media Access Control (MAC) layer functions within bidirectional ring networks. [cite: Tsiang et al.]
3. IEEE Draft P802.1w/D10, "Amendment 2-Rapid Reconfiguration" (March 26, 2001). This draft indicates the industry's focus on rapid reconfiguration in network environments. [cite: IEEE Draft P802.1w/D10]
4. General knowledge of network redundancy techniques. A PHOSITA would be aware that, in redundant systems, backup devices often assume the identity (e.g., MAC address) of a failed primary device for quick failover.

Motivation to Combine and Explanation of Obviousness:
Building upon the dual-module gateway described in Combination 1, a PHOSITA would be motivated to ensure the failover process is as rapid and seamless as possible, minimizing service disruption.

1. MAC-based Forwarding: Given that packet forwarding in a bidirectional ring network (like RPR/SRP) relies heavily on MAC addresses for directing traffic to specific nodes or gateways (as taught by Tsiang et al.), it would be a natural design choice to implement the gateway's receiving logic based on MAC addresses. [cite: Tsiang et al.]
2. Rapid Failover with MAC Addresses: To achieve rapid failover where the surviving module immediately captures traffic intended for the failed module, a PHOSITA would recognize the advantage of preconfiguring both gateway modules with not only their own unique MAC address but also the MAC address of their peer. This is a common strategy in redundant network elements to facilitate fast takeover.
3. Efficiency and Speed: This preconfiguration eliminates the need for dynamic address learning or complex re-provisioning during a fault event, allowing the operational module to instantly recognize and capture packets destined for the failed module's MAC address upon receiving a fault indication. This aligns with the broader industry trend of rapid reconfiguration, as evidenced by references like IEEE Draft P802.1w/D10. [cite: IEEE Draft P802.1w/D10]

Therefore, implementing MAC address preconfiguration for rapid failover in the context of the dual-module gateway with directional load sharing would have been an obvious design choice for a PHOSITA seeking to optimize protection speed and efficiency, rendering claims 5, 9, 15, and 21 obvious.

Dependent claims 2, 4, 6, 7, 8, 10, 11, 12, 14, 17, 18, 19, 20, 22, 23, and 24 further elaborate on aspects such as transmitting in both directions, wrapping traffic, interconnecting access/trunk networks or other network types. These elements are either explicitly taught as "known in the art" within US7054264 itself (e.g., wrapping/steering traffic) [cite: US7054264 Description, 0012], or represent conventional network configurations and functionalities that would be obvious to a PHOSITA once the underlying independent claims are considered obvious.