FILS-Enabled WLAN Active Scanning for Reduced Setup Time
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing wireless local area network (WLAN) technologies face challenges in reducing the long initial link setup time, particularly due to inefficient active scanning methods that result in increased network overhead and delay, especially in scenarios where multiple devices attempt to access the network simultaneously.
Innovation Solution
The method involves transmitting information on whether a station (STA) supports fast initial link setup (FILS) to the FILS access point (AP), allowing the AP to determine the optimal method for transmitting probe response frames, thereby enabling rapid initial link setup by broadcasting or unicasting probe responses based on STA capabilities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If traditional active scanning is used in WLAN, then all STAs can access the network, but the initial link setup time becomes significantly long and network overhead increases
Solution Approach 1:
The patent segments the STA population into two distinct groups: FILS-capable STAs and legacy STAs. The AP handles these segments differently by sending broadcast probe responses to FILS STAs (reducing overhead) and unicast probe responses to legacy STAs (maintaining compatibility). This segmentation resolves the contradiction by allowing optimized fast setup for capable devices while preserving support for all devices.
Solution Approach 2:
The patent introduces dynamic behavior where the AP adapts its probe response transmission method based on STA capabilities. The AP determines whether to send broadcast or unicast probe responses dynamically based on whether the receiving STA supports FILS. This dynamic adaptation enables the system to achieve fast initial link setup for FILS STAs while maintaining compatibility with legacy STAs, resolving the time-loss versus complexity contradiction.
2Productivity
If multiple STAs transmit probe requests simultaneously, then network discovery is faster, but probe response collisions increase and delay access
Solution Approach 1:
The patent implements preliminary action by having STAs include their FILS capability information in the probe request frame before receiving the probe response. This allows the AP to pre-determine the appropriate response method (broadcast or unicast) based on the STA's capabilities, preventing response collisions and ensuring reliable delivery while maintaining fast network discovery speed.
Solution Approach 2:
The patent uses feedback mechanisms where the AP receives probe requests with FILS capability information and adjusts its probe response transmission strategy accordingly. The AP monitors incoming probe requests and dynamically selects broadcast or unicast mode based on the FILS capability feedback from STAs, resolving the contradiction between fast discovery and reliable delivery.
3Adaptability or versatility
If broadcast probe responses are sent to all STAs, then legacy STAs can receive responses, but network overhead and congestion increase
Solution Approach 1:
The patent applies local quality by differentiating the probe response transmission method based on the target STA's location in the capability spectrum. FILS-capable STAs receive broadcast probe responses (reducing overall network traffic), while legacy STAs receive unicast probe responses (ensuring compatibility). This localized differentiation resolves the contradiction between versatility and traffic volume by optimizing for each STA type's specific requirements.
Solution Approach 2:
The patent changes the transmission parameter (broadcast vs. unicast) based on the STA's FILS capability parameter. When the AP detects a FILS-capable STA, it changes from unicast to broadcast mode for probe responses, reducing network traffic volume. For legacy STAs, it maintains unicast mode to ensure compatibility. This parameter change strategy resolves the contradiction between adaptability and traffic quantity.
Data Source
Figure 1(A)~1(B)
Figure 2
Figure 3(A)~3(B)
AI summary
Disclosed are a method and an apparatus for active scanning in a wireless LAN. The method for active scanning in a wireless LAN may comprise the steps of: a first station(STA) transmitting a first probe request frame to an access point (AP); and a first STA receiving a probe response frame from the AP, wherein the probe response frame is a response for the probe request frame, and the first probe request frame comprises fast initial link setup(FILS) capability information which can indicate whether the first STA supports FILS.