Fast Initial Link Setup (FILS) defined in the Institute of Electrical and Electronics Engineers (IEEE) specification 802.11ai, the disclosure of which is hereby incorporated by reference in its entirety herein, is an ongoing effort within the IEEE 802.11 series of specifications, commonly referred to as Wi-Fi, to reduce the initial link setup time between a client and an access point (access point) down to less than 100 ms. Wi-Fi does offers the high-speed data but the initial link setup may take more than a few seconds, which is often enough time to cause unwanted interruptions in a voice or video call. The link setup time is the entire time it takes a client to establish a link or other association with an access point before it can start sending and receiving data. The link setup process may include four stages: access point discovery, network discovery, authentication and association and DHCP/IP address assignment. The link setup process can take as long as 5 seconds today and can be a problem, especially for the many Wi-Fi users today that are on the move.
A client driving in the city served by many Wi-Fi hotspots and on a voice call may travel rapidly through a coverage area of one access point to another with the amount of time spent in the blanket of each access point being quite low. In the few seconds the client spends in the coverage area of a single access point, the initial link setup would need to be completed quickly to take advantage of the available Wi-Fi connection and have a seamless call. (Of course, the client may be able to a cellular connection or link, however, providing seamless access without such a switch may be beneficial to avoid cellular services fees and to take advantage of Wi-Fi becoming ubiquitous.) Another use case (often termed to ‘Tokyo Central Station’ case) can arise when a large number of Wi-Fi users enter (and exit) a coverage area of an access point in an ESS in a short period of time. Both exemplary scenarios experience scanning delays as a majority of the delay in link setup.
Enhanced scanning mechanisms are being considered to address the corresponding delays in initial link setup. Two such mechanism are known as:
Filter List: The client, through its probe request frame explicitly identifies which access points it does not want to hear back from, such as through filter performed based on information collected from a previous scan. This ability to identify whether to stop receiving a probe response frame from any particular access point reduces scanning time and Wi-Fi pollution with the elimination of subsequent and unnecessary probe response frames being transmitted from the corresponding access point(s).
Comprehensive Probe Response: A comprehensive probe response (CPR) occurs when a master access point in a coverage area transmits a probe response instead of individual probe responses being transmitted from each access point in the coverage area. The single, comprehensive probe response decreases scanning time by limiting the number of transmitted probe responses
Some access points may facilitate wireless signaling corresponding with that described in the CableLabs technical report for Wireless Wi-Fi entitled Wi-Fi Radio Resource Management (RRM)/Self Organizing Networks (SON) Technical Report (WR-TR-RRM-SON-V01-140926) and the CableLabs specification entitled Wi-Fi Provisioning Framework Specification (WR-SP-WR-SP-WiFi-MGMT-I06-160111), the disclosures of which are hereby incorporated by reference in their entireties herein. One goal of Wi-Fi Radio Resource Management (RRM)/Self Organizing Networks (SON) is to provide efficient operator managed and vendor interoperable Wi-Fi radio performance in the presence of large and dynamically changing numbers of access points and heavy user traffic.
One non-limiting aspect of the present invention contemplates leveraging a Wi-Fi SON server in a cloud/network that updates access point RF configurations based upon changes in local user traffic or networks topologies to reduce initial link setup time, such as to facilitate the FILS sought after with IEEE 802.11ai.