Fixed Mobile Convergence. VoWiFi Requirements. May 2006. Fanny Mlinarsky Founder and CTO Azimuth Systems



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Transcription:

Fixed Mobile Convergence VoWiFi Requirements Fanny Mlinarsky Founder and CTO Azimuth Systems May 2006

The Convergence Vision is One Device Indoors and Out... with Data, Voice and Video Slide 2

The Sky Appears to be the Limit on VoWi-Fi Handset Market Growth Every major handset provider and every major service provider are thought to have converged handset programs (ABI, 9/05) By 2009, at more than 105M units, phones will be the largest single platform for Wi-Fi technology (IDC, 3/05) Source: Infonetics Research, July 2005 Slide 3

Market Dynamics INITIAL FOCUS PAST YEAR COMING SOON 4G LAN Data LAN Data VoWLAN Simple Mesh Cellular WiFi Data Cellular WiFi Handover (GAN) LAN Data VoWLAN Metro Mesh Cellular WiFi Data Cellular WiFi Handover (GAN) Video within Home Video to Handset SIP/IMS 2003/2004 2005 2008 Slide 4

IMS Infrastructure for FMC IP Multimedia Subsystem (IMS) -- the infrastructure for Fixed Mobile Convergence (FMC) IP Network Fixed Mobile Convergence Mobile Fixed Slide 5

Standards for FMC 3GPP- IMS GAN/UMA 2G VCC 3G/4G I-WLAN (no handoff) IEEE 802.21 802.11u Proprietary GSM BSS MobileIGNITE Plain IETF SIP solutions just IP and firewalls BSC A-, Gb- Mobile Core Network A-, Gb- GANC Slide 6 GAN GAN = generic access network UMA = unlicensed mobile access VCC = Voice Call Continuity I-WLAN = Interworking-WLAN IMS = internet multimedia subsystem MobileIgnite = Mobile Integrated Go-to-Market Network IP Telephony Experience FOMA = freedom of mobile multimedia access SCCAN = seamless converged communication across networks

GAN / UMA GAN / UMA GSM Infrastructure GANC GAN / UMA GSM/WiFi phones CDMA/WiFi phones WLAN UMA/GAN is here today GSM is widespread throughout the world Phones from Nokia, Samsung, BenQ P50, Sony-Ericsson, i-mate and others IMS VCC is coming for non-gsm 3G networks 3GPP VCC (voice call continuity) standard for cell/wifi handoff one year away Targets 3G networks such as UMTS, CDMA-2000, WCDMA, etc. Slide 7

GSM Network Architecture BTS (Base Transceiver System) BSC (Base Station Controller) MSC (Mobile Switching Centre) VLR (Visitor Location Register) HLR (Home Location Register) SGSN (Serving GPRS Support Node) GGSN (Gateway GPRS Support Node) Slide 8

UMA/GAN Architecture GAN / UMA GSM Infrastructure GANC WLAN In a UMA/GAN, Wi-Fi and VoIP are integrated with GSM Core network by means of GANC (generic access network controller). GANC presents itself to the Core Network as just another BSC. Slide 9

Voice Network Requirements Minimize bursty packet loss by controlling roaming time 802.11r Fast Roaming 802.11k Radio Resource Measurement (RRM) 802.11i Pre-authentication Maintain isochronous nature of voice packet streams by controlling delay, jitter and packet loss 802.11e Quality of Service (QoS) prioritization Slide 10

How Do You Know How Well Your Phone Works? Data Communications Test Data Voice Video Wireless Test Packet Loss Signal Strength Jitter Can You Hear Me Now? Latency Throughput Power Channel Emulation Frequency Testing Packets Over Air to Mobile Users Requires Combining Wireless and Data Communications Test Slide 11

Standards and Interoperability are Critical to Industry Growth Advancing standards to enhance real time applications on Wi-Fi Making strides to certify and promote VoWi-Fi Slide 12

IEEE 802.11 and the Wi-Fi Alliance are Tackling Standards for VoWi-Fi Maintain Isochronous Nature of Voice Packet Streams by Controlling Delay, Jitter and Packet Loss IEEE 802.11e Quality of Service (QoS) prioritization => Will be Wi-Fi Alliance Certified through WMM, VoWi-Fi SOHO and enterprise Minimize Bursty Packet Loss Due to Roaming IEEE 802.11r Fast Roaming IEEE 802.11k Radio Resource Measurement (RRM) => Will be Wi-Fi Alliance Certified through VoWi-Fi enterprise testing Manage Power Consumption IEEE 802.11e Power-save => Will be Wi-Fi Alliance Certified through APSD testing Testing VoWi-Fi Solutions Wi-Fi Alliance testing expanded with standard ASD Testing IEEE 802.11T testing will help standardize industry testing Slide 13

IEEE 802.11 Standards MAC PHY 802.11 ( 99) MAC + 2Mbps PHY 802.11e QoS 802.11h DFS & TPC 802.11i Security 802.11f Inter AP 802.11a ( 99) 54 Mbps 5GHz PHY 802.11s Mesh 802.11r Fast Roam 802.11p WAVE 802.11k RRM 802.11m Maint 802.11u WIEN SG 802.11v WNM 802.11w Mgt frames 802.11n High Throughput (>100 Mbps) 802.11T Test Methods 802.11b ( 99) 11 Mbps 2.4GHz PHY 802.11g 54 Mbps 2.4GHz PHY Current Work Published Slide 14

IEEE 802.11 Task Groups TGK - RADIO RESOURCE MEASUREMENTS TGM - 802.11 STANDARD REVISION TGN - HIGH THROUGHPUT TGP - WIRELESS ACCESS FOR THE VEHICULAR ENVIRONMENT TGR - FAST ROAMING TGS - ESS MESH NETWORKING TGT - WIRELESS PERFORMANCE TGU - INTERWORKING WITH EXTERNAL NETWORKS TGV - WIRELESS NETWORK MANAGEMENT TGW - PROTECTED MANAGEMENT FRAMES Slide 15

IEEE 802.11 WLAN Roadmap 1Q06 2Q06 3Q06 4Q06 1Q07 Q07 3Q07 4Q07 802.11k Radio Measurement 802.11r Fast Roaming Oct 05 EWC (enhanced wireless consortium) 802.11p Vehicle 802.11n High Speed 802.11T Test 802.11u Interworking 802.11s Mesh IEEE Standards Board Approval (expected) http://grouper.ieee.org/groups/802/11/802.11_timelines.htm 03/03/05 Slide 16

TGn High Throughput Mixed-mode interoperability with 802.11a/b/g networks provides enhanced performance while maintaining communication with legacy devices PHY transmission rates up to 600Mbps supports applications requiring high data rates (transmitting multiple HDTV streams) reduces battery drain by minimizing the time required to send and receive data streams Enhanced efficiency MAC with frame aggregation brings actual throughput closer to the raw PHY rate, providing end users with at least 100 Mbps application level bandwidth Use of 2.4GHz and 5GHz unlicensed bands matches the frequency plan of existing 802.11 devices 20MHz and 40MHz channel support doubles the wireless spectrum over legacy 802.11 networks to enhance performance Enhanced range via multiple antennas and advanced coding provides for a wider coverage area with consistent wireless speeds Slide 17

TGt Milestones Approval: Nov 2008 Primary metrics directly impact user experience Secondary metrics indirectly impact user experience Framework section describes how metrics should be used to predict application performance Data applications such as file transfers, email, etc. Streaming video applications Voice applications Bandwidth-critical Data Streaming Delaysensitive Time-critical Slide 18

TGt Tests Conducted Throughput versus attenuation Transmit rate adaptation Antenna diversity Adjacent channel interference BSS transition time Fast BSS transition time Receiver sensitivity in a conducted environment Unicast intra-bss throughput Unicast ESS throughput Multicast forwarding rate Client association rate Client database capacity Power consumption Over-the-air Throughput versus attenuation in an OTA environment Throughput versus range in an OTA environment Slide 19

Slide 20

WFA Voice over Wi-Fi Certifications for home and enterprise use cases Home basic WMM + WPA Enterprise must do fast roaming and enterprise security Home certification January 2006 Enterprise must wait for TGr/TGk to be more solid Performance testing includes latency, jitter, packet loss Slide 21

Applications Specific Device (ASD) Testing at the Wi-Fi Alliance ADEPT-WFA Includes wireless and wired: Sniffer Analysis of Test Results Specialized test stimuli ASDUT ASDUT running ASD Agent with ASD Traffic Agent Test bed APs Test traffic Vendor-Specific Communications interface (wired or wireless) Vendorproprietary control protocol PC running ASD Control Agent ASD API Control Over Ethernet Azimuth Test Manager Including DUT config and control Traffic endpoint Test coordination Results collection Pass/Fail Analysis Slide 22

Wi-Fi Alliance WCC (WiFi Cellular Convergence) Certification Radio RF performance (TIS, TRP*) Conducted and over the air tests Use testmac in AP mode Anechoic chamber Free-space antenna pattern Antenna pattern against phantom head DUT * Total Radiated Power (TRP) Total Isotropic Sensitivity (TIS) Slide 23

Voice Quality ITU-T Voice Quality Standards MOS (mean opinion score) uses a wide range of human subjects to provide a subjective quality score (ITU-T P.800) PESQ (perceptual speech quality measure) sends a voice pattern across a network and then compares received pattern to the original pattern and computes the quality rating (ITU-T P.862) E-Model computes Rating Factor or R-Factor as a function of delay and packet loss; R-Factor directly translates into MOS (ITU-T G.107) Slide 24

ITU-T PESQ Model Slide 25

ITU-T E-Model (G.107) Slide 26

E-Model Parameters Parameter Abbr. Unit Default Value Permitted Range Send Loudness Rating SLR db +8 0 +18 Receive Loudness Rating RLR db +2-5 +14 Sidetone Masking Rating STMR db 15 10 20 Listener Sidetone Rating LSTR db 18 13 23 D-Value of Telephone, Send Side Ds - 3-3 +3 D-Value of Telephone Receive Side Dr - 3-3 +3 Talker Echo Loudness Rating TELR db 65 5 65 Weighted Echo Path Loss WEPL db 110 5... 110 Mean one-way Delay of the Echo Path T ms 0 0 500 Round-Trip Delay in a 4-wire Loop Tr ms 0 0 1000 Absolute Delay in echo-free Connections Ta ms 0 0 500 Number of Quantization Distortion Units qdu - 1 1 14 Equipment Impairment Factor Ie - 0 0 40 Packet-loss Robustness Factor Bpl - 1 1 40 Random Packet-loss Probability Ppl % 0 0 20 Circuit Noise referred to 0 dbr-point Nc dbmop -70-80 -40 Noise Floor at the Receive Side Nfor dbmp -64 - Room Noise at the Send Side Ps db(a) 35 35 85 Room Noise at the Receive Side Pr db(a) 35 35 85 Advantage Factor A - 0 0 20 G.107 Default values and permitted ranges for the parameters Slide 27

R-Factor to MOS Conversion Slide 28

VoWiFi Performance QoS vs. capacity QoS vs. range QoS vs. WiFi-WiFi roam QoS vs. WiFi-cell roam Slide 29

VoWiFi Call Capacity Test Test Description: Capacity vs. QoS Performance of Wi-Fi infrastructure Features Emulate voice traffic from multiple phones Emulate or bridge background data traffic Measure delay, jitter and packet loss* vs. number of calls and background traffic Test Diagram Test Results * Per IETF RFCs 2544, 2889 Slide 30

VoWiFi Call Capacity Test Test Description: Capacity vs. QoS Performance of Wi-Fi infrastructure Features + click to enlarge Test Diagram Test Results Verifies the ability of infrastructure to prioritize voice traffic and to reject or redirect calls when capacity is reached Test APs, wireless switches and other infrastructure devices Measures infrastructure capacity vs. R-Factor and MOS quality scores computed from the measured packet loss rate, delay and jitter Slide 31

VoWiFi Call Capacity Test Test Description: Capacity vs. QoS Performance of Wi-Fi infrastructure Features + click to enlarge Test Diagram Test Results Verifies the ability of infrastructure to prioritize voice traffic and to reject or redirect calls when capacity is reached Test APs, wireless switches and other infrastructure devices Measures infrastructure capacity vs. R-Factor and MOS quality scores computed from the measured packet loss rate, delay and jitter Slide 32

VoWiFi Call Capacity Test Test Description: Capacity vs. QoS Performance of Wi-Fi infrastructure Features + click to enlarge Test Diagram Test Results Verifies the ability of infrastructure to prioritize voice traffic and to reject or redirect calls when capacity is reached Test APs, wireless switches and other infrastructure devices Measures infrastructure capacity vs. R-Factor and MOS quality scores computed from the measured packet loss rate, delay and jitter Slide 33

VoWiFi Call Capacity Test Test Description: Capacity vs. QoS Performance of Wi-Fi infrastructure Features + click to enlarge Test Diagram Test Results Verifies the ability of infrastructure to prioritize voice traffic and to reject or redirect calls when capacity is reached Test APs, wireless switches and other infrastructure devices Measures infrastructure capacity vs. R-Factor and MOS quality scores computed from the measured packet loss rate, delay and jitter Slide 34

VoWiFi Call Capacity Test Test Description: Capacity vs. QoS Performance of Wi-Fi infrastructure Features + click to enlarge Test Diagram Test Results Verifies the ability of infrastructure to prioritize voice traffic and to reject or redirect calls when capacity is reached Test APs, wireless switches and other infrastructure devices Measures infrastructure capacity vs. R-Factor and MOS quality scores computed from the measured packet loss rate, delay and jitter Slide 35

QoS and Capacity in a WiFi Mesh Network Self configuration and self healing Throughput and QoS vs. number of users Throughput and QoS vs. number of hops Voice and video quality, packet loss, delay and jitter vs. number of hops, number of user, traffic load per user, etc. Throughput Voice Quality Video Quality QoS settings Security settings 802.11a,b,g,n Motion Fail-over # hops # users per hop Traffic load per user Slide 36

Mesh Test Configuration Client emulation Slide 37

VoWiFi Handset Range Test Test Description: Quality of Voice Transmission over Wi-Fi as a Function of Path Loss, Roaming and Traffic Load Features + click to enlarge Test Diagram Test Results Automatically validates Voice over Wi-Fi performance in minutes Standard benchmark test to analyze rate adaptation of handset and AP pair Shows R-Factor and MOS performance of real time voice stream - measures packet loss, delay and jitter to formulate MOS score Precise RF control allows for measurement of true range performance based on actual WiFienabled handsets Slide 38

VoWiFi Handset Range Test Test Description: Quality of Voice Transmission over Wi-Fi as a Function of Path Loss, Roaming and Traffic Load Features + click to enlarge Test Diagram Test Results Automatically validates Voice over Wi-Fi performance in minutes Standard benchmark test to analyze rate adaptation of handset and AP pair Shows R-Factor and MOS performance of real time voice stream - measures packet loss, delay and jitter to formulate MOS score Precise RF control allows for measurement of true range performance based on actual WiFienabled handsets Slide 39

VoWiFi Handset Range Test Test Description: Quality of Voice Transmission over Wi-Fi as a Function of Path Loss, Roaming and Traffic Load Features + click to enlarge Test Diagram Test Results Automatically validates Voice over Wi-Fi performance in minutes Standard benchmark test to analyze rate adaptation of handset and AP pair Shows R-Factor and MOS performance of real time voice stream - measures packet loss, delay and jitter to formulate MOS score Precise RF control allows for measurement of true range performance based on actual WiFienabled handsets Slide 40

VoWiFi Handset Range Test Test Description: Quality of Voice Transmission over Wi-Fi as a Function of Path Loss, Roaming and Traffic Load Features + click to enlarge Test Diagram Test Results Automatically validates Voice over Wi-Fi performance in minutes Standard benchmark test to analyze rate adaptation of handset and AP pair Shows R-Factor and MOS performance of real time voice stream - measures packet loss, delay and jitter to formulate MOS score Precise RF control allows for measurement of true range performance based on actual WiFienabled handsets Slide 41

VoWiFi Roaming Test Test Description: Roaming Performance of Wi-Fi Handsets Features Measures the roaming time and quality of voice vs. roam Detailed breakdown of the roaming time helps optimize roaming algorithm Motion and fail-over roaming emulation of real world scenarios Precise RF control and distributed monitoring present a wealth of information on handset performance as a function of motion Test Diagram Test Results Slide 42

Roaming Process max AP1 AP2 AP1 Path to AP1 Atten min Test cycle Data rate transition Path to AP2 t ASSOCIATE t TRANSITION t DATA t SCAN Last data packet before roam t ROAM First data packet after roam Slide 43

Roaming Benchmark Tests Test Description: Motion and Fail-Over Roaming Performance Test Features Measures client roaming time precisely and automatically Distributed monitoring analyzes pre and post roam Velocity and cell overlap are userprogrammable Detailed analysis depicts each phase of the roaming process including rate adaptation, scan and association time Test Diagram Test Results Slide 44

Roaming Benchmark Tests Test Description: Motion and Fail-Over Roaming Performance Test Features Measures client roaming time precisely and automatically Distributed monitoring analyzes pre and post roam Velocity and cell overlap are userprogrammable Detailed analysis depicts each phase of the roaming process including rate adaptation, scan and association time Test Diagram Test Results Slide 45

Summary A Growing Number of Demanding Applications are Using Wi-Fi Devices and systems need to be more reliable Performance, interoperability, and device compliance is critical Emerging Standards are Driving Wi-Fi in QoS Intensive Applications (such as VoWiFi) Continued Success of Wi-Fi Requires: Products that conform to the new standards Products and services that meet consumer expectations Automated Test Tools Facilitate Development of High Performance, Standards-Compliant products Yes, I hear you! Slide 46