Neighbor AP Discovery for Protected BSS Roaming

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing access points (APs) face difficulties in being discovered by stations (STAs) when roaming due to changes in parameters such as Service Set Identifier (SSID) or Basic Service Set Identifier (BSSID) to prevent malicious devices, leading to failed associations.

Innovation Solution

An AP provides a report to associated STAs with information about neighboring APs, including their BSSIDs and the time until they rotate their BSSIDs, enabling STAs to anticipate and successfully associate with new APs during roaming.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If an AP hides parameters such as SSID or BSSID to prevent malicious devices from mimicking the AP, then security is improved, but other APs and STAs encounter difficulty discovering the AP

Engineering Contradiction:

ImprovesecurityVSAvoiddiscovery difficulty

Core Design Contradiction:

ReliabilityVSDifficulty of detecting and measuring

Solution Approach 1:

The system performs preliminary action by having the current AP provide neighbor AP information to STAs before the STAs need to discover and associate with neighboring APs. This includes providing BSSID lists and optionally BSSID change indicators, so that STAs are pre-informed of neighboring AP identities and can quickly associate when roaming without needing to perform lengthy discovery procedures.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The current AP acts as an intermediary between the hidden neighbor APs and the STAs. Instead of STAs directly discovering hidden neighbor APs (which is difficult), the current AP receives and processes neighbor AP information and relays it to STAs through beacon frames or other communication channels, thus mediating the discovery process while maintaining the hidden APs' security.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If an AP changes BSSID to prevent malicious devices, then security is improved, but STAs may fail to discover the AP when roaming

Engineering Contradiction:

ImprovesecurityVSAvoidroaming success rate

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The system implements feedback by providing STAs with information about neighbor APs including their BSSIDs and potentially BSSID change indicators. This feedback loop allows STAs to be informed of neighboring AP identities in advance, enabling them to successfully associate with new APs during roaming even when those APs change their BSSIDs for security purposes.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The system performs preliminary action by pre-providing STAs with neighbor AP BSSID information before roaming occurs. This allows STAs to have advance knowledge of neighboring AP identifiers and can prepare for association, ensuring successful roaming connectivity even when neighbor APs implement BSSID changes for security.

Inventive Principle:

Principle #10Preliminary action

3Difficulty of detecting and measuring

If an AP provides detailed information about neighboring APs, then STA discovery capability is improved, but information overhead increases

Engineering Contradiction:

Improvediscovery capabilityVSAvoidinformation overhead

Core Design Contradiction:

Difficulty of detecting and measuringVSLoss of information

Solution Approach 1:

The system applies the extraction principle by selectively providing only the essential neighbor AP information that STAs need for discovery and association, rather than transmitting all possible AP parameters. This includes providing BSSID lists and optionally BSSID change indicators, which are the critical elements for enabling STA discovery while minimizing unnecessary information overhead in beacon frames or communication protocols.

Inventive Principle:

Principle #2Taking out (Extraction)

Data Source

PatentUS20260067673A1NEIGHBOR DISCOVERY MECHANISMS FOR PROTECTED BASIC SERVICE SETS (BSSs)

Publication Date: 2026.03.05 CISCO TECHNOLOGY INC

AI summary

An AP may provide information about a neighbor AP to a STA before roaming to assist with the STA associating with the neighbor AP. The information may include a BSSID of the neighbor AP and a time until the neighbor AP rotates the BSSID. If the STA fails to discover the neighbor AP while the STA is roaming, the STA can request more information about the neighbor AP from the AP.