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Wi-Fi 6.pptx

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Wi-Fi 6.pptx

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This presentation briefly describes the Wi-Fi 6 Technology or the latest wi-fi: IEEE802.11ax which I have used at IIT Madras to present and explain my course work(reading assignment). here I have covered all the problems, solutions, and benefits of wi-fi 6, how Wi-Fi evolved, standards, security, advantages, and innovations.

This presentation briefly describes the Wi-Fi 6 Technology or the latest wi-fi: IEEE802.11ax which I have used at IIT Madras to present and explain my course work(reading assignment). here I have covered all the problems, solutions, and benefits of wi-fi 6, how Wi-Fi evolved, standards, security, advantages, and innovations.

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Wi-Fi 6.pptx

  1. 1. Name: Kaustubh Mani Roll no: ee22e006 Instructor: Avhishek Chatterjee
  2. 2. Overview of Wi-Fi • Wi-Fi, orWireless Fidelity, based on the IEEE 802.11 standards for WLAN. • Allows us to connect to the Internet from anywhere without wires. • Internet connectivity occurs through a wireless router. • Send and receive data indoors and out; anywhere within the range of a base station by Radio waves.
  3. 3. Evolution of IEEE 802.11 standards: Over the past 20 years, IEEE 802.11 commonly referred to asWi-Fi has evolved from 2 Mbps to over gigabit speeds., a 1,000-fold increase in throughput.
  4. 4. 802.11ax AT A GLANCE • Contains a new PHY protocol with higher modulation and coding schemes. • Adoption of an OFDMA approach. • Unlike its predecessor, the 802.11ac, 802.11ax is a dual-band technology working in the 2.4 GHz and 5 GHz frequencies. • In 802.11ax,OFDMA is frame-based : an MU frame contains data to/from different users and various tones are assigned to the users for the entire frame duration. • periodic channel reservations (namely, the QuietTime periods) can be used to protect direct link communications. • Introducing OFDMA inWi-Fi affects the other MAC and PHY functionality. • Support up to 8x8 MU-MIMO. • 1024 QAM-a high SNR and 25% high data rate compared to 256 QAM . • also supports the transmission of multiple streams to a single client or multiple clients simultaneously.
  5. 5. Problems: • Number and variety of devices is increasing. • Another challenge comes from the diminishing asymmetry in traffic patterns. • power consumption for battery-operated devices. • To improve the Quality of Service (QoS) for multiple users. • suffer from frequency selective interference, which significantly impairs the practically achievable rates. • prone to the Doppler effect mainly caused by reflections from fast moving objects such as cars and trains. • Quadrupling the symbol duration means 4 times more calculations at the receiver side, bring problems for low-costWi-Fi devices. • in dense networks, load balancing is also an important problem.
  6. 6. Why we need it? • problems associated with dense, high-traffic environments such as airports, stadiums, trains and offices. • increases the n0 of streams to 12 across the 2.4 and 5 GHz bands, whereasWi-Fi 5 has a limit of 8. • provides higher connection speed and cost effective. • more paths to communicate with yourWi-Fi router. • designed for the Smart Home. • ideal for 4K/8K UHD streaming. • Multi-user techniques, such as MU-MIMO and OFDMA, have been improved to increase the network efficiency and network capacity. While the previous standards supported MU-MIMO for downlink connections, Wi-Fi 6 supports 8x8 connections for both uplink and downlink.
  7. 7. OFDMA • Brings an improvement over prior versions ofWi-Fi that use orthogonal frequency division multiplexing (OFDM). It subdivides theWi-Fi channel into smaller frequency. • OFDMA channel consists of a total 256 subcarriers which can be grouped into smaller subchannels known as resource units( RUs). • OFDMA is much more efficient than EDCA. • Enables an access point(AP) to synchronise communication (uplink and downlink ) with multiple individual clients. • for backward compatibility ,WI-FI 6 radios still support OFDM.
  8. 8. Proposed solution: • comes with 12 antenna chains for dual band (8x8 in 5GHz / 4x4 in 2.4GHz), helping it deliver best-in-class throughput ,Wider Coverage. • 802.11ax contains a new PHY protocol with higher modulation and coding schemes • amendment also introduces new modulation techniques 1024 QAM in addition to legacy BPSK, 16-QAM, 64-QAM, and 256-QAM. • To improve the resistance to high mobility, the amendment proposes to periodically insert in the PHY packet payload mi ambles, i.e., copies of the HE-LTF field.
  9. 9. • to improve the performance in case of dense networks such as airports, stadiums, trains and offices : BSS Color, QuietTime Period, Channel Bonding and Preamble Puncturing,Virtualization, Load Balancing. • for low-costWi-Fi devices : provides the possibility to extend the tail of a frame with an extension. • 802.11ax also allows performing a UL MU transmission just after a DL MU transmission and extends this idea by allowing an STA to doze during UL transmissions or theTXOP of another STA in the same BSS. • proposes an additional way for acknowledging UL MU transmissions by sending new Multi STA BlockACK (BA) frames. • proposes OMAX ,a novel OFDMA-based MAC protocol .
  10. 10. OVERLAPPING BSS MANAGEMENTAND SPATIAL REUSE • to improve the performance in case of dense networks. • BSS coloring: inherited from 802.11ac and 802.11ah, allows to distinguish inter- and intra BSS frames. • QTP : allows a STA to request the AP for a QTP which is a series of periodic time intervals of equal duration used for ad hoc or direct links operation. • Virtualization:One of the widespread features in modern APs is the support for multiple “virtual” APs (VAPs).This means that a single physical device can create multiple independent BSSs. • Opportunistic power save (OPS) : mechanism allows anAP to split a beacon interval into several subintervals • Microsleep operation, which enables a STA to switch off its radio just for the duration of an alien frame; i.e., they can switch off their radio interface during some transmissions, when they cannot be involved in the frame exchange process. • modulations generate a palette of data rates with a maximum of 9.6 Gbps. • supports bidirectional MU-MIMO for both uplink and downlink capabilities.
  11. 11. Performance Analysis: • With OFDMA, adjacent subcarriers (tones) are grouped together into a resource unit (RU) and a sender can choose the best RU for each particular receiver, which actually results in higher Signal-to-Interference-plus-Noise Ratio (SINR), Modulation and Coding Scheme (MCS) and throughput. • OFDMA provides a 6 times higher throughput than legacy DCF(Distributed Coordination Function).
  12. 12. Power management and security • Legacy Power Management : two state – Awake and doze. • In the awake state, an STA can transmit and receive frames, while in the doze state, its radio is switched off. An active STA is always awake. • Microsleep:802.11ax extends this idea by allowing an STA to doze during UL transmissions or the TXOP of another STA in the same BSS. • TWT (Target wakeup time): In order to minimize the contention between STAs and to reduce power consumption,TGax adapted theTWT mechanism. • WPA3: also known as Wi-Fi Protected Access 3, is the third iteration of a security certification program developed by theWi-Fi Alliance.WPA3 is the latest, updated implementation of WPA2. • WPA3 protects against offline password guesses by allowing a user only one guess, making the user have to interact with the Wi-Fi device directly, meaning they would have to be physically present every time they want to guess the password
  13. 13. Benefits: • introduces the Multiple BSSID support, which allows the sending of identical information for all the BSSs simultaneously. • Better Security • Better Mobility • High speed even when congested. • Increased battery life. • TWT :In order to minimize the contention between STAs and to reduce power consumption. Drawback : the synchronization ofTWT SPs between STAs is beyond the scope of the standard. • Opportunistic Power Save :(OPS) mechanism allows an AP to split a beacon interval into several subintervals
  14. 14. Conclusion:

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