1. IP Networking & MEDIACOM 2004 Workshop 24 - 27 April 2001 Geneva Characterising End to End Quality of Service in TIPHON Systems Characterising End to End Quality of Service in TIPHON Systems Helmut Schink Siemens AG

2. IP Networking & MEDIACOM 2004 Workshop 24 - 27 April 2001 Geneva Approach to Characterizing Multimedia QoS  QoS is defined subjectively as perceived by the user,  Classes include guaranteed quality (statistically) and unguaranteed (best effort).  A number of QoS Service Classes are defined,  It is end to end (e.g. mouth to ear for speech),

3. IP Networking & MEDIACOM 2004 Workshop 24 - 27 April 2001 Geneva ITU-T G.109 Voice Quality Categories ITU-T G.109 defines categories of voice quality for conventional 3.1 KHz telephony in terms of R

4. IP Networking & MEDIACOM 2004 Workshop 24 - 27 April 2001 Geneva Definition of TIPHON Speech QoS Classes  BEST: providies voice quality better than PSTN, using wideband audio (eg 7 kHz) codecs, over QoS-engineered IP networks  HIGH: provides voice quality comparable to PSTN, over QoS-engineered IP networks  MEDIUM: provides voice quality comparable to mobile telephony, over QoS-engineered IP networks  BEST EFFORT: provides usable voice quality, but not guaranteed, over non QoS-engineered IP networks

5. IP Networking & MEDIACOM 2004 Workshop 24 - 27 April 2001 Geneva TIPHON QoS Class Performance Metrics  End-to-end delay, Each TIPHON class is defined by three performance metrics  Listening Speech Quality (one-way, non conversational),  Overall Transmission Quality Rating (R) (combines codec performance and effects of network impairments into one subjective metric via G.107 Emodel )

6. IP Networking & MEDIACOM 2004 Workshop 24 - 27 April 2001 Geneva The TIPHON Speech QoS Classes Undefined Better than G.711 Listener Speech Quality (One-way Non- conversational) Equivalent or better than GSM-FR Equivalent or better than G.726 at 32 kbit/s Class Guaranteed (Best) Guaranteed (High) Guaranteed (Medium) Unguaranteed (Best Effort) < 400ms* < 150ms < 100ms End-to-end Delay (G.114) > 50*> 80 N.A. Overall Transmission Quality Rating (R) > 70 * Target

7. IP Networking & MEDIACOM 2004 Workshop 24 - 27 April 2001 Geneva BEST HIGH MEDIUM BEST EFFORT BESTHIGHMEDIUMLOWPOOR G.109 Performance Categories R-value 100 90 80 70 60 50 Relationship between TIPHON Service Classes & R Value

8. IP Networking & MEDIACOM 2004 Workshop 24 - 27 April 2001 Geneva Parameters Determining QoS in IP Networks

9. IP Networking & MEDIACOM 2004 Workshop 24 - 27 April 2001 Geneva Factors Influencing QoS Usual factors:  Levels, echoes, delay, noise, terminal acoustics. Specific Packet Related Factors:  Delay Jitter  Packet Loss,  Codec performance.

10. IP Networking & MEDIACOM 2004 Workshop 24 - 27 April 2001 Geneva Inter-relationship of QoS Factors Codec Performance Network Factors Network Delay Network Packet Loss Network Jitter Overall Delay Application Factors Overall Packet Loss Jitter Buffers Perceived Quality QoS Service Level

11. IP Networking & MEDIACOM 2004 Workshop 24 - 27 April 2001 Geneva Network Packet Loss, Mean Delay, Delay Variation SERVICE APPLICATION TRANSPORT QoS Service Class Codec, Frames per Packet, Frame Size, Jitter Buffer Size, Overall Delay, Overall Packet Loss, FEC (Redundancy) Derivation of Transport QoS Parameters

12. IP Networking & MEDIACOM 2004 Workshop 24 - 27 April 2001 Geneva 0% Packet Loss Command/ control (eg Telnet, Interactive games) Conversational voice and video Voice/video messaging Streaming audio/video Transactions (eg E-commerce, Web-browsing, E-mail access) Paging, Downloads (eg FTP, still image) Fax Background (eg Usenet) 5% 100 msec1 sec10 sec100 sec Zero loss InteractiveResponsiveTimelyNon-critical Delay Extension to Multimedia QoS Classes TIPHON VoIP requirements address this quadrant from a user perspective, packet loss and delay are the fundamental performance metrics for all multimedia services

13. IP Networking & MEDIACOM 2004 Workshop 24 - 27 April 2001 Geneva Further Information TR 101 329 - Part 2 TIPHON; Quality of Service (QoS) Classes TIPHON Web sitehttp://www.etsi.fr/tiphon/ Access to Documentation http://docbox.etsi.org/tech-org/ tiphon/Document/tiphon/07-drafts/wg5/