Overview of Wi-Fi Dr. Srikanth Subramanian CKO, Nanocell Networks www.nanocellnetworks.com Wi-Fi A Wireless Success Story Wi-Fi present in all laptops/aps Wi-Fi Traffic trends Source: Cisco percentage 100 50 0 Wi-Fi in Phones and tablets 2010 2015 2018 Wi-Fi Wired Wi-Fi's next wave presence in all CE devices (IOT) Wi-Fi Calling Significant traffic to come from noncomputing devices
IEEE 802.11 Web browsing, E-mail, YouTube TCP/UDP IP IEEE 802.11 Application Layer Transport Layer Network Layer Data Link Layer Physical Layer Remains the same as in wired scenarios Define PHY and MAC layers for WLAN operation Emulate wired LAN (Ethernet) Role of the Wi-Fi Alliance Interoperability of WLAN products Certification Market trends Inputs to IEEE for upgrading standards Promotions Make WLANs easy to use, publicize, security & other features of WLANs Standards Use 802.11 radios for enabling new applications
Wi-Fi RF Bands Sensor/ smart grid Outdoor use in some countries Sub 1 2.4 2.5 3.65 4.9 5.0 5.8 60 Frequency () Most popular Wi-Fi band Japan specific Gradually becoming mainstream Future band Popular Bluetooth band Unlicensed band in most important markets More PAN and video centric than LAN Wi-Fi Network Types Infrastructure Network Ad-hoc Networks Mesh Networks Used in homes, offices & hotspots 802.11 ad-hoc Wi-Fi Direct Used in widearea/large campus deployments Used in some gaming devices Wi-Fi alliance initiative for easy to use peer-topeer connections
Wi-Fi Technology Evolution Part 1 (PHY) IEEE Standard 802.11 (1997) 802.11b (1999) 802.11a (1999) 802.11g (2003) 802.11n (2009) 802.11ac (2013E) 80 MHz (160 MHz optional) 802.11ad 1.8 Max. channel bandwidth 22 MHz 22 MHz 20 MHz 20 MHz 40 MHz Technology Max. PHY layer Data rate FHSS/D SSS DSSS (CCK) OFDM OFDM Backward compatibility is always kept in perspective 2 Mbps 11 Mbps 54 Mbps 54 Mbps MIMO + OFDM 600 Mbps MIMO (SU/MU) + OFDM Beam forming +SC/OFDM Upto 7 Gbps Up to 7 Gbps Spectrum 2.4 2.4 5 2.4 2.4 5 5 60 Wi-Fi Technology Evolutions Part 2 (MAC) Efficiency 802.11n QoS 802.11e Roaming 802.11r Features External networks 802.11 u Management 802.11k/v Many extensions have been incorporated in 802.11 main standard. Security 802.11i Support in products is not universal for all extensions.
Wi-Fi Deployments Carrier enabled Homes Peer to peer Offices 11n client Multiband Wi-Fi Hotspots 11b/g client 11a/b/g/n AP Wi-Fi and IoT Power not a big issue in some cases Reliable connection to Internet Add Wi- Fi/Retro fit Wi-Fi Wi-Fi AP present in homes, hotspot, retail,enterprise etc. Planned Wi-Fi deployments have good coverage People comfortable with Wi-Fi New sub 1 solution (Wi-Fi HaLow) announced for low-power devices Cost effective solutions available
Wi-Fi calling - Motivation? Roaming charges on cellular leads to users using OTT apps (skype/viber over Wi-Fi) Cannot use the cellular phone number Internet AP PSTN Wi-Fi and cellular radios present enb/nb/bts Poor signal in many indoor locations Lots of voice calls made from indoor locations Wi-Fi calling Use of Wi-Fi for calling /receiving using phone credentials (No apps) Operator Supported Internet Any AP which allows access OK AP enb/nb/bts Core Network PSTN Handover to cellular to be taken care
WiFi Aware No connection for alert Alerts about service Power efficiency kept in perspective App to get alerts Beacon like alerts If interested in service connections can be established WFA certification program based on neighbor awareness networking 802.11 The Real Story!! Real-life Wi-Fi traffic..difficult to aggregate in highdensity scenarios Advances of 802.11 PHY. are practically useless.. We are benefitting by better radio and CPUs in products
Wi-Fi Sucks!! Source: Aruba Networks LTE in Unlicensed Spectrum Control signaling Mobility User data Primary Cell EPC Unlicensed Spectrum- 5 Combined use of BW for data Secondary Cell Aggregation of Licensed + Unlicensed Anchor in the licensed carrier 16
New Standard 802.11ax Majority of deployments will evolve towards high density scenarios in the near future.. To increase the real world throughput achieved by users. To improve power efficiency for the battery powered devices. PAR aims for 4 times higher average throughput at MAC in a dense Wi-Fi environment than previous generation..5-10 times likely Amendment to 802.11 for operations in between 1 to 6 frequency bands. Focus primarily on 2.4 and 5. 802.11ax Key technologies and approaches DL A-MPDU Trigger AP A-MPDU to STA4 AP A-MPDU to STA1 AP A-MPDU to STA2 AP A-MPDU to STA3 Trigger Trigger Trigger Trigger UL A-MPDU STA6 A-MPDU to AP STA4 A-MPDU to AP STA1 A-MPDU to AP STA2 A-MPDU to AP STA5 A-MPDU to AP STA3 A-MPDU to AP Multiuser Transmission; OFDMA, MU-MIMO RaiesdCCAmax DynamicValue Spatial reuse Dynamic threshold; plus power control..good coexistence
LTE and Wi-Fi together LWA and LWIP Licensed Band EPC Aggregating Wi-Fi and LTE @ radio level Traffic through both LTE and Wi-Fi Both colocated and non colocated cases of enb and Wi-Fi AP considered Unlicensed Band Carrier grade AP Needs interface to communicate with LTE enb LTE R13 specifications completed 19 Future Trends in Wi-Fi Ripe for Innovation; Wi-Fi Aware Potential Bluetooth replacement Peer-topeer access Home and Internet access 2.4 & 5 Wi-Fi Adopt higher speed Wi-Fi Displays, Set top boxes Interactions with cellular Enterprise network access Wi-Fi Calling More usage of 5 Wi-Fi 60 Wi-Fi usage Seamless transfer Smooth interaction with carrier LWA and LWIP