802.11ai - Fast initial link setup (FILS) ============================================= .. toctree:: :maxdepth: 1 :hidden: :includehidden: 802_11ai/802_11ai 802_11ai/mac_functions 802_11ai/mac_timings 802_11ai/packet_formats 802_11ai/power_save 802_11ai/interoperability 802_11ai/physical_rates 802_11ai/ppdu 802_11ai/channels 802_11ai/PHYs 802.11ai enables Fast Initial Link Setup (FILS) to dramatically reduce Wi-Fi connection and authentication times for quick, secure access in dense and mobile environments. .. list-table:: :widths: 20 60 20 :header-rows: 1 * - Category - Description - Use Case * - MAC Functions - Introduces Fast Initial Link Setup (FILS) procedures, enabling rapid authentication and association. - Reducing connection setup times for fast and seamless network access * - MAC Timings - Optimizes timing for quick exchange of management frames during initial link setup. - Accelerating client association in dense and mobile environments * - Packet Formats - Defines new frame formats and elements supporting FILS and fast roaming. - Efficient management frame exchange for quick network access * - Power Save - Supports fast handoff with minimal power consumption during frequent connection changes. - Enhancing battery life in mobile devices during rapid network transitions * - Interoperability - Compatible with existing 802.11 standards while introducing fast link setup enhancements. - Seamless integration into legacy and modern WLAN deployments * - Physical Rates - Relies on underlying PHY layers; focuses on MAC enhancements rather than new PHY rates. - Enables fast setup without affecting data throughput capabilities * - PPDU - Uses existing PPDU formats; no major changes in physical layer signaling. - Maintains PHY compatibility while speeding up link establishment * - Channels - Operates on standard 2.4 GHz and 5 GHz bands. - Supports rapid access across common Wi-Fi frequency bands * - PHY Overview - No significant PHY modifications; improvements primarily at MAC and management layers. - Facilitates quick, secure connections leveraging existing physical technologies .. tab-set:: .. tab-item:: 802.11ai (Fast Initial Link Setup) **Standard:** IEEE 802.11ai (2016) **Main Features:** - Enables Fast Initial Link Setup (FILS) for rapid authentication and association - Reduces connection setup times to under 100 milliseconds - Optimizes management frame exchanges for faster roaming - Supports secure and efficient handoffs with minimal latency - Compatible with existing PHY layers (2.4 GHz and 5 GHz bands) - Improves user experience in dense and mobile environments **Use Cases:** - High-mobility scenarios such as public transport and enterprise Wi-Fi - Dense networks requiring fast and secure client onboarding - IoT and mobile devices needing quick network access with low power - Seamless roaming in large-scale deployments like campuses and stadiums **Related Concepts:** - Fast Initial Link Setup (FILS) procedures - Optimized MAC and management frame exchanges - Secure and efficient authentication and association - Enhancements for low latency and power saving during link setup .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: What You Will Learn in This Section **Explore the details of 802.11ai and its impact on fast Wi-Fi connectivity:** * :ref:`Learnings in this section <802_11ai_step1>` * :ref:`Terminology <802_11ai_step2>` * :ref:`Version Info <802_11ai_step3>` * :ref:`802_11ai Version&IEEE Details <802_11ai_step4>` * :ref:`802_11ai Basic Setup on Ubuntu using IPv4 <802_11ai_step5>` * :ref:`802_11ai Basic Setup on Ubuntu using IPv6 <802_11ai_step6>` * :ref:`Reference links <802_11ai_step16>` .. button-link:: ./802_11ai/802_11ai.html :color: primary :shadow: :expand: Jump to "802.11ai Basics" .. tab-set:: .. tab-item:: 802.11ai MAC Functions **Standard:** IEEE 802.11ai (2016) **Main Features:** - Provides enhanced MAC mechanisms for Fast Initial Link Setup (FILS) - Supports rapid authentication and association frame exchanges - Manages efficient scheduling for multi-user access with low latency - Enables advanced power saving through Target Wake Time (TWT) - Coordinates error detection and retransmission optimized for speed - Works closely with PHY layer for accelerated secure connection setup **Use Cases:** - Enabling fast, secure Wi-Fi connections in high-density and mobile environments - Minimizing connection setup delay for IoT and mobile devices - Supporting seamless network onboarding and roaming **Related Functions:** - FILS frame management and fast authentication - Multi-user scheduling and contention reduction - Power saving with TWT integration - Enhanced error handling and retransmission .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: What You Will Learn in This Section **Explore the details of 802.11ai MAC Functions:** * :ref:`Reference links ` .. button-link:: ./802_11ai/mac_functions.html :color: primary :shadow: :expand: Jump to "802.11ai MAC Functions" .. tab-set:: .. tab-item:: 802.11ai MAC Timings **Standard:** IEEE 802.11ai (2016) **Main Features:** - Defines optimized timing parameters for fast initial link setup - Includes shortened interframe spaces for rapid frame exchanges - Specifies slot times and contention windows tuned for FILS procedures - Supports Target Wake Time (TWT) for scheduled power saving wake-ups - Minimizes latency through efficient retransmission and collision avoidance - Synchronizes MAC and PHY timing for quick and secure connections **Use Cases:** - Accelerating connection setup in public hotspots and enterprise WLANs - Reducing latency for mobile and IoT device onboarding - Improving network responsiveness in dense, fast-moving scenarios **Related Timing Parameters:** - Shortened Interframe Spaces (SIFS and others) - Contention window adjustments for FILS - TWT scheduling for power efficiency - Slot timing optimized for low latency .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: What You Will Learn in This Section **Explore the details of 802.11ai MAC Timings:** * :ref:`Reference links ` .. button-link:: ./802_11ai/mac_timings.html :color: primary :shadow: :expand: Jump to "802.11ai MAC Timings" .. tab-set:: .. tab-item:: 802.11ai Packet Formats **Standard:** IEEE 802.11ai (2016) **Main Features:** - Defines frame structures for Fast Initial Link Setup (FILS) exchanges - Introduces new management and control frames to support rapid authentication - Supports enhanced frame aggregation and multiplexing for efficiency - Uses TLV (Type-Length-Value) elements for flexible and extensible messaging - Enables secure and fast frame exchanges with minimal overhead - Maintains backward compatibility with legacy 802.11 management frames **Use Cases:** - Accelerating secure connection setup in dense or public Wi-Fi networks - Facilitating quick network onboarding for mobile and IoT devices - Supporting low-latency, high-throughput authentication and association **Related Frame Types:** - FILS Authentication and Association frames - Management frames with enhanced security elements - Control frames for scheduling and power management - TLV-encoded extensions for flexible communication .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: What You Will Learn in This Section **Explore the details of 802.11ai Packet Formats:** * :ref:`Reference links ` .. button-link:: ./802_11ai/packet_formats.html :color: primary :shadow: :expand: Jump to "802.11ai Packet Formats" .. tab-set:: .. tab-item:: 802.11ai Power Saving Mechanisms **Standard:** IEEE 802.11ai (2016) **Main Features:** - Implements advanced power saving with Target Wake Time (TWT) scheduling - Supports network-assisted power management for faster and efficient wake/sleep cycles - Allows devices to minimize active radio time during initial setup and roaming - Coordinates with fast authentication mechanisms to reduce power consumption - Integrates with legacy power save features for backward compatibility - Enhances battery life for mobile, IoT, and battery-powered devices in Wi-Fi networks **Use Cases:** - Extending battery life in dense public and enterprise Wi-Fi environments - Reducing power use during rapid connection setup and roaming - Enabling efficient wake/sleep coordination for IoT and mobile clients **Related Mechanisms:** - Target Wake Time (TWT) - Network-assisted wake/sleep coordination - Power-efficient authentication and association procedures .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: What You Will Learn in This Section **Explore the details of 802.11ai Power Saving mechanisms:** * :ref:`Reference links ` .. button-link:: ./802_11ai/power_save.html :color: primary :shadow: :expand: Jump to "802.11ai Power Saving" .. tab-set:: .. tab-item:: 802.11ai Interoperability **Standard:** IEEE 802.11ai (2016) **Main Features:** - Fully interoperable with existing 802.11 standards and legacy devices - Extends management and authentication frames to support Fast Initial Link Setup (FILS) - Supports coexistence with devices not implementing 802.11ai enhancements - Enables optional adoption of fast authentication and power-saving mechanisms - Ensures backward compatibility to prevent disruption in mixed environments - Integrates seamlessly with other 802.11 amendments such as 802.11ax and 802.11r **Use Cases:** - Accelerating secure network access while maintaining compatibility with legacy devices - Deploying fast link setup in dense or public Wi-Fi networks without disrupting existing clients - Gradual rollout of 802.11ai features alongside established network protocols **Related Mechanisms:** - Fast Initial Link Setup (FILS) with fallback to standard authentication - Target Wake Time (TWT) optional power saving - Management frame extensions with backward compatibility .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: What You Will Learn in This Section **Explore the details of 802.11ai Interoperability mechanisms:** * :ref:`Reference links ` .. button-link:: ./802_11ai/interoperability.html :color: primary :shadow: :expand: Jump to "802.11ai Interoperability" .. tab-set:: .. tab-item:: 802.11ai Physical Rates **Standard:** IEEE 802.11ai (2016) **Main Features:** - Uses physical rates defined by underlying 802.11 PHY standards, primarily 802.11ax (Wi-Fi 6) - Does not modify PHY or physical rate specifications directly - Supports high data rates up to 10 Gbps using 1024-QAM, OFDMA, and wide bandwidth channels - Enhances rate adaptation through fast link setup and network-assisted scheduling - Facilitates rapid link establishment while maintaining efficient PHY utilization - Compatible with existing rate control and PHY adaptation algorithms in devices **Use Cases:** - Supporting ultra-fast network access with minimal delay - Optimizing PHY rate usage during quick connection setup - Enhancing overall user experience in dense, high-throughput Wi-Fi environments **Related Concepts:** - PHY rate adaptation in Wi-Fi 6 and related amendments - Integration with fast authentication and scheduling features - Maintaining compatibility with legacy and future PHY standards .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: What You Will Learn in This Section **Explore the details of 802.11ai Physical Rates:** * :ref:`physical_rates in 802.11ai ` * :ref:`Reference links ` .. button-link:: ./802_11ai/physical_rates.html :color: primary :shadow: :expand: Jump to "802.11ai Physical Rates" .. tab-set:: .. tab-item:: 802.11ai PPDU **Standard:** IEEE 802.11ai (2016) **Main Features:** - Uses standard PPDU formats defined by underlying PHY layers (e.g., 802.11ax/Wi-Fi 6) - Maintains compatibility with base 802.11 PPDU structures for seamless integration - Carries Fast Initial Link Setup (FILS) authentication and management frames within standard PPDU payloads - Supports multi-user transmissions and advanced preambles for fast synchronization - Enables rapid frame exchanges critical for fast secure network access - Ensures backward compatibility with devices not supporting 802.11ai extensions **Use Cases:** - Accelerating authentication and association via fast frame exchanges - Supporting dense network environments with efficient multi-user PPDU handling - Maintaining interoperability during fast link setup procedures **Related Concepts:** - FILS frame encapsulation within PPDU data payloads - PHY-MAC coordination for fast initial link setup - Use of enhanced preambles for quicker synchronization .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: What You Will Learn in This Section **Explore the details of 802.11ai PPDU:** * :ref:`Reference links ` .. button-link:: ./802_11ai/ppdu.html :color: primary :shadow: :expand: Jump to "802.11ai PPDU" .. tab-set:: .. tab-item:: 802.11ai Channels **Standard:** IEEE 802.11ai (2016) **Main Features:** - Operates within frequency bands and channel plans defined by underlying PHY standards such as 802.11ax - Supports operation in 2.4 GHz, 5 GHz, and optionally 6 GHz bands with Wi-Fi 6E compatibility - Does not introduce new channels but leverages existing Wi-Fi channels for fast link setup - Facilitates rapid network access while minimizing interference through channel selection - Supports dynamic channel use aligned with network conditions and client capabilities - Integrates with other amendments for channel coordination and network optimization **Use Cases:** - Rapid channel acquisition for fast authentication and association - Minimizing channel contention during dense network access attempts - Enhancing overall spectrum efficiency during initial link setup **Related Concepts:** - Standard Wi-Fi channel plans and bandwidths (20/40/80/160 MHz) - Dynamic channel selection and frequency agility - Integration with network-assisted channel management protocols .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: What You Will Learn in This Section **Explore the details of 802.11ai Channels:** * :ref:`List of channels ` * :ref:`List of channel widths ` * :ref:`List of Bands ` * :ref:`Reference links ` .. button-link:: ./802_11ai/channels.html :color: primary :shadow: :expand: Jump to "802.11ai Channels" .. tab-set:: .. tab-item:: 802.11ai PHY **Standard:** IEEE 802.11ai (2016) **Main Features:** - Builds upon PHY features from 802.11ax (Wi-Fi 6) and earlier 802.11 standards - Inherits modulation, coding, and channel characteristics for high efficiency and low latency - Supports OFDMA and MU-MIMO for multi-user fast link establishment - Utilizes PHY-layer enhancements for rapid synchronization and reduced setup time - No changes to base PHY layers; all 802.11ai features are MAC and management layer extensions - Leverages PHY measurements and feedback for optimized fast authentication and link setup **Use Cases:** - Enabling ultra-fast secure network access with PHY-level efficiency - Supporting high-density environments with rapid PHY resource allocation - Improving overall wireless experience during initial association phases **Related Concepts:** - OFDMA and MU-MIMO PHY techniques for efficiency - PHY-layer signal processing aiding fast initial link setup - Use of standard modulation and coding schemes in Wi-Fi 6 .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: What You Will Learn in This Section **Explore the details of 802.11ai PHY:** * :ref:`Reference links ` .. button-link:: ./802_11ai/phy.html :color: primary :shadow: :expand: Jump to "802.11ai PHY"