Untersuchung Adaptiver Multimedia-Anwendungen über UMTS

1. Untersuchung Adaptiver Multimedia-Anwendungen über UMTS Michael Link, Stefan Gruhl, Markus Bauer, Michael SöllnerGlobal Wireless Systems ResearchBell Labs, Nürnberg mlink@lucent.com ITG Workshop “IP in Telekommunikationsnetzen”26.01.2001 Lucent Technologies - Proprietary

2. IP UMTSRadio LinkEmulator IP 3G Wireless Multimedia Personal Information Management Unified Messaging Video Streaming 3G Wireless Network IP MultimediaApplication Clients Content Access MultimediaApplication Servers M-Commerce

3. Outline • UMTS QoS Framework • UMTS Demonstrator • Objectives and Concepts • Architecture • QoS Flows Concept • Radio Link Emulation • Configuration & Monitoring Tool • Application Example

4. Application Middleware CN EDGE CN Gateway UTRAN MT Service Provider Network / Internet TE UMTS QoS Framework Client Server End-to-End Application: QoS requirements & adaptation API UMTS UMTS GPRS Hiperlan …. UMTS End-to-End Bearer Service TE/MT Local Bearer Service UMTS Bearer Service: UMTS QoS External Bearer Service Radio Access Bearer Service CN Bearer Service Radio Bearer Service Iu Bearer Service Backbone Bearer Service

5. UMTS Demonstrator - Objectives • Joint evaluation and optimization of UMTS packet data services and multimedia applications • Real-time UMTS radio link emulation is required for the evaluation of • interactive applications, • control loop performance of adaptive applications. • Support of standard applications: • IP interface • QoS support for QoS-unaware IP applications

6. UMTS Demonstrator - Concepts • Real-time UMTS radio link emulation running on Linux PC, multimedia applications on Laptops, all connected by LAN • Layer 1/2 UMTS radio protocol stack emulation for user plane data traffic, including: • RLC segmentation & ARQ • MAC scheduling • PHY bit-error injection • QoS flow concept: individual QoS setting for each TCP or UDP data flow WLAN LAN Application Client Application Server “UMTS Proxy”

7. Configuration & Monitoring Tool Multimedia Data, Control & Signaling Multimedia Data, Control & Signaling UDP TCP IP UDP TCP IP UMTS Radio Link Emulation UMTS Demonstrator - Architecture Application Client Application Server UMTS Proxy Configurator UMTS Proxy IP Kernel Module LAN LAN IP Dispatcher UMTS Module IP Address Translation & Checksum

8. QoS Flows Concept Problem: current applications do not support QoS procedures. Each TCP or UDP connection is treated as an individual flow: • Flows are distinguished by source/destination IP address and port numbers. • To each flow, an individual service is assigned: • A service is defined by UMTS Traffic Class and maximum bit-rate. • Services are mapped to UMTS radio link protocol parameters. • Example: differentiation between TCP call setup and UDP data streaming

9. Emulated UMTS Services Mapping of UMTS Traffic Class and bit-rate to radio protocol parameters:

10. UMTS Radio Link Emulation IP packet from IP translation to IP Flow identification Database: Service parameters Frame error model parameters Error gap distributions IP queues UMTS Layers: RLC MAC PHY RLC error control & re-assembly RLCsegmentation on demand retransmission requests MAC scheduling CRC flags frame PHY frame error model & bit error injection

11. Scenarios Events Frame Error Model Error Model Database Parameters if frame error Bit Error Model Bit error pattern PHY Emulation • Real-time emulation required • Nested model for the output of the channel decoder • Error model parameters: • derived from link-level simulations • database for various scenarios

12. Configuration & Monitoring Tool

13. Example - Video Streaming IP-based streaming & videophone applications: • Some but limited delay • UDP transport  packet loss • Application specific control loops: • error control by buffering, retransmission, and slow bitrate adaptation • designed for Internet congestion • inefficient for wireless link • Standards & implementations: • RTP/RTCP, RTSP • Real Video Streaming • Windows Media Streaming • MS NetMeeting (H.323)

14. Applications Windows Media Streaming: multiple bitrate stream: 26/40/60/80/120/200/300 kbps(audio: 8 kbps) buffer:  3 seconds Real Video Streaming: multiple bitrate stream:20/34/45/80/150/225/350/450 kbps(audio: 5-32 kbps) buffer:  3 seconds UMTS Proxy Frame error model: PB = 0.01, LB = 2, Service: Streaming 128 kbps, RLC ARQ off Streaming 128 kbps, RLC ARQ on Streaming 64 kbps, RLC ARQ on buffer: 3 seconds (48 kB / 24 kB) Example Session - Parameters

15. Example Session - Traces Windows Media Streaming Real Video Streaming

16. Conclusion The UMTS Demonstrator is an integrated, real-time UMTS radio link emulator + application monitoring tool. Application Server UMTSRadio LinkEmulator Application Client IP IP Configuration & Monitoring Tool

17. Backup Slides • Ongoing Work • Protocol Context • IP Interface • UMTS Traffic Classes and QoS Attributes • Supported Applications • References

18. UMTS Demonstrator - Ongoing Work • Physical layer simulations and measurements for the PHY database • UMTS shared channels and MAC scheduling • Signalling delay emulation • QoS API for wireless optimised applications

19. emulated UMTS Demonstrator - Protocol Context UMTS Bearer Service Radio Bearer Service Radio Protocols Iu Protocols CN Edge CN Gateway L3 PDCP PDCP RLC RLC L2 MAC MAC PHY PHY PHY FPAALATM FPAALATM L1 Buffer Iub Iu Uu(Radio) MT GGSN Node B RNC SGSN UE UTRAN CN

20. IP Interface • IP Kernel Module: • Modification of Linux IP kernel • Table of Client/Server IP address pairs: IP packets arriving at the UMTS Proxy from these hosts are forwarded to the UMTS Module. • IP header address translation: • Uplink: Client  Proxy to Proxy  Server • Downlink: Server  Proxy to Proxy  Client • Client and Server both assume the corresponding peer is running on the Proxy host. • Optional: IP address translation within TCP payload (H.323, FTP) • Checksum re-calculation: • Before error-injection: injected bit-errors result in checksum errors at the receiver and TCP or UDP packet delay or loss, respectively. • After error-injection: forwarding of bit-errors into an error resilient application.

21. UMTS Traffic Classes

22. UMTS QoS Attributes • traffic class • max. bitrate • guaranteed bitrate • SDU delivery order • maximum SDU size • SDU format • SDU error ratio • residual BER • delivery of erroneous SDUs • SDU transfer delay • traffic handling priority • allocation/retention priority

23. Supported Applications • Standard IP applications (ftp, telnet, etc.) • Web browsing • MS NetMeeting • Real Video Streaming • Windows Media Services • Video enhanced messaging (“miLife”) ... most IP based multimedia application are configurable to run through the UMTS Proxy!

24. References • S. Gruhl, A. Echihabi, T. Rachidi, M. Link, and M.Söllner, “A Demonstrator for Real-time Multimedia Sessions over 3rd Generation Wireless Networks”, International Conference on Multimedia and Expo (ICME) 2000, New York, 30 Jul. - 2 Aug. 2000. • 3GPP TS 23.107: “QoS Concept and Architecture” • 3GPP TS 25.201: “Physical layer - general description” • 3GPP TS 25.211: “Physical channels and mapping of transport channels onto physical channels (FDD)” • 3GPP TS 25.212: “Multiplexing and channel coding (FDD)” • 3GPP TS 25.214: “Physical layer procedures (FDD)” • 3GPP TS 25.301: “Radio Interface Protocol Architecture” • 3GPP TS 25.302: “Services Provided by the Physical Layer” • 3GPP TS 25.401: “UTRAN Overall Description” • 3GPP TR 25.944, “Channel coding and multiplexing examples,” • GSMA ISG RP-000304: “Typical Radio Parameter Sets Version 1.2”, TSG-RAN Meeting #8, Düsseldorf, Germany, 21 - 23 June 2000 • ITU-T SG 16 Q15-F-45: “Common conditions for video performance evaluation in H.324/M error-prone systems”