Failover VLAN Redundancy for PMP Backhaul Reliability

Solution Overview

Problem

The failure of a single concentration node in a Point-to-Multipoint (PMP) wireless Ethernet backhaul network disrupts traffic for associated access nodes and user equipment, leading to a loss of upstream and downstream communication, as there is no redundancy to divert traffic to another node.

Innovation Solution

Implementing active-active or active-standby virtual local area networks (VLANs) between concentration nodes to ensure traffic redundancy and diversity, allowing traffic from an access node to be actively provided to and from both concentration nodes, thereby minimizing the impact of a node failure by establishing a failover VLAN that can reroute traffic in case of a failure.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a single concentration node is used to provide backhaul coverage to multiple access nodes, then device complexity and cost are reduced, but reliability deteriorates because failure of the concentration node causes complete loss of backhaul service

Engineering Contradiction:

Improvebackhaul service continuityVSAvoidnetwork architecture complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent implements different operational modes for different concentration nodes based on their geographic coverage relationships. Concentration nodes are categorized into standalone nodes and overlapping nodes, with the latter having different traffic handling capabilities. This local differentiation allows the system to achieve redundancy only where geographically necessary, rather than uniformly across all nodes.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The system pre-establishes multiple traffic engineering (TE) tunnels between concentration nodes before failures occur. These tunnels are configured in advance as part of the network architecture, so that when a concentration node fails, pre-computed backup paths are immediately activated without requiring real-time routing calculations, enabling rapid failover.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 3:

The patent introduces intermediate concentration nodes as mediators that can receive traffic from failed concentration nodes and forward it to the core network. These intermediary nodes act as backup relay points, allowing traffic to be rerouted through them when primary concentration nodes fail, thus maintaining service continuity.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If coverage areas of concentration nodes overlap to provide mutual coverage, then reliability improves through redundancy, but device complexity increases due to multiple concentration nodes and traffic routing requirements

Engineering Contradiction:

Improvebackhaul service continuityVSAvoidnumber of concentration nodes

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent implements different operational modes for different concentration nodes based on their geographic coverage relationships. Concentration nodes are categorized into standalone nodes and overlapping nodes, with the latter having different traffic handling capabilities. This local differentiation allows the system to achieve redundancy only where geographically necessary, rather than uniformly across all nodes.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The system dynamically adjusts traffic routing based on the operational status of concentration nodes. When a concentration node fails, the system automatically reconfigures traffic paths using pre-established TE tunnels, transitioning from direct routing to indirect routing through intermediary nodes. This dynamic adaptation maintains service continuity without requiring manual intervention.

Inventive Principle:

Principle #15Dynamics

3Reliability

If traffic is actively provided to both concentration nodes from access nodes, then redundancy is achieved, but device complexity and bandwidth requirements increase

Engineering Contradiction:

Improvetraffic flow redundancyVSAvoidbandwidth capacity

Core Design Contradiction:

ReliabilityVSQuantity of substance

Solution Approach 1:

The system dynamically adjusts traffic routing based on the operational status of concentration nodes. When a concentration node fails, the system automatically reconfigures traffic paths using pre-established TE tunnels, transitioning from direct routing to indirect routing through intermediary nodes. This dynamic adaptation maintains service continuity without requiring manual intervention.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent ensures continuous traffic flow by pre-establishing backup TE tunnels that remain idle during normal operation but are immediately activated upon failure. This approach maintains the capability for redundant traffic flow without requiring both paths to be actively utilized simultaneously, thus avoiding unnecessary bandwidth consumption during normal operation.

Inventive Principle:

Principle #20Continuity of useful action

Data Source

PatentUS8665706B2Redundancy in point-to-multipoint (PMP) backhaul networks

Publication Date: 2014.03.04 VERIZON PATENT & LICENSING INC

AI summary

A device establishes a failover virtual local area network (VLAN) with a first concentration node, a first Ethernet backhaul router, and an access node of a first Ethernet backhaul coverage area. The device also receives, via the first Ethernet backhaul router, an indication of a failure of a second concentration node of a second Ethernet backhaul coverage area intersecting with the first Ethernet backhaul coverage area. The device further enables, based on the failure indication, a switchover of traffic, associated with the second concentration node, to the device and via the failover VLAN.