Theoretical and Practical Aspects of Triple Play

Transcription

1 Theoretical and Practical Aspects of Triple Play 1. Introduction 2. Network and Protocol Architecture for Triple Play 3. Characteristics and Parameters of Triple Play 4. Main QoS and QoE Methods and Standards 5. Dimensioning in a Triple-Play Area 6. Conclusion and Future Work

2 1. Introduction Interactive services (e.g. Speech, E-Learning) Distribution services (e.g. Audio or Video on demand) Real-time services (e.g. VoIP, Video Conference) Non real-time services (e.g. WWW, FTP, ) Audio services (e.g. IP-Audio, IP-Radio) Video services (e.g. IPTV) Data services (e.g. TFTP, Mail-Box) Triple Play services

3 1. Introduction Type of service Delay Jitter Bandwidth Speech low low low Data transmission high high high Transmission of Message Tolerances about: high high medium Audio on demand medium medium medium Video on demand medium medium high Radio low low medium TV low low high

4 1. Introduction Properties of the IP transport platform non-secure datagram service no flow control no real-time properties no guaranteed bandwidth new architecture and protocols necessary! QoS ensurement necessary! QoS measurement necessary!

5 2. Network Architecture for VoIP (IETF: SIP) Proxy - Server Proxy - Server IP Network Location - Server Redirect - Server SIP - Terminal SIP - Terminal

6 2. Protocol Architecture for VoIP (IETF: SIP)

7 2. Network Architecture for IP-Audio & IP-Radio

8 2. Protocol Architecture for IP-Audio & IP-Radio

9 2. Network Architecture for IPTV

10 2. Protocol Architecture for IPTV

11 2. Protocol Architecture for IPTV Video Data Audio Data MPEG- 2 Video-Encoder MPEG- 2 Audio-Encoder Packetizer Packetizer Video PES Audio PES PS Mux Program Stream Transport Stream Data Packetizer TS Mux Data PES MPEG- 2 System

12 2. Protocol Architecture for IPTV Network PID NIT CAT PID_01... SDT... PAT PID_00 Prog.0 Prog.1 Prog.2 Prog.n EIT PID0 PID1 PID2 PIDn Actual present/following PMT Prog.1 Stream.a PIDa Stream.b PIDb Stream.c PIDc Stream.n PIDn PMT Prog.2 Stream.a PIDa Stream.b PIDb Stream.c PIDc Stream.n PIDn

13 2. Protocol Architecture for IPTV

14 3. Characteristics and Parameters of VoIP VoIP communication uses a unicast connection in full-duplex operation. The traffic in VoIP communication features the CBR character. A voice connection with the G.711 codec uses approx. 160 kbps of the bandwidth. A voice connection with the G codec uses approx. 40 kbps of the bandwidth. Using the G.711 codec, the packet size is approx. 214 bytes, of which 160 bytes are used for the data field (20 ms speech samples). Using the G codec, the packet size is approx 80 bytes, of which 24 bytes are used for the data field (30 ms speech samples). An increase in the efficiency of VoIP transmission can only be achieved if the capacity of the compensation buffer is sized accordingly.

15 3. Characteristics and Parameters of IP-Audio & IP-Radio An IP-audio or IP-radio session can be established using live-streaming or on-demand streaming protocols. An IP-audio or IP-radio transmission uses a unicast connection in simplex operation. The traffic in IP-audio or IP-radio communication normally has the CBR character. The typical packet size of the service is in the range of 400 to 1000 bytes. This service typically uses a bandwidth of 50 to 100 kbps. An audio connection established according to MP3 (high quality) uses approx. 320 kbps of the bandwidth. An audio player, e.g. Windows Player or RealAudio Player is needed for playback. An increase in the efficiency of radio transmission can only be achieved if the capacity of the compensation buffer is sized accordingly.

16 3. Characteristics and Parameters of IPTV Signalling is done in IPTV with a unicast connection. IPTV communication itself uses a multicast connection in simplex operation. The traffic of IPTV communication has the CBR character. An SDTV IPTV connection established according to H.264 uses approx. 3 Mbps of the bandwidth. An HDTV IPTV connection established according to H.264 uses approx. 10 Mbps of the bandwidth. A transport packet is always 188 bytes long. 7 transport packets are bundled into a group and transmitted in either a UDP or an RTP packet (1350 bytes). An increase in the efficiency of IPTV transmission can only be achieved if the capacity of the compensation buffer in the STB is sized accordingly.

17 4. Main QoS and QoE Methods and Standards Methods for measuring the quality of services Subjective analysis => QoE Objective analysis => QoS Simple methods using network performance parameters Complex methods using reference models

18 4. Main QoS and QoE Methods and Standards MOS: Mean Opinion Score According to the standard ITU-T P.800 Based on the subjective appraisal of a number of subjects MOS values as the benchmarks for quality of services MOS Value Service Quality 5 excellent 4 good 3 fair 2 poor 1 bad

19 4. Main QoS and QoE Methods and Standards QoS based on network capacity: Connection time Bandwidth Packet loss Delay Jitter QoS based on video capacity: Program clock reference jitter (PCR Jitter) Synchronization loss Continuity error CRC error

20 4. Main QoS and QoE Methods and Standards PESQ: Perceptual Evaluation of Speech Quality According to the standard ITU-T P.862 Based on the psychoacoustic properties of the human sense of hearing PEAQ: Perceptual Evaluation of Audio Quality According to the standard ITU-R BS.1387 Based on the psychoacoustic properties of the human sense of hearing PEVQ: Perceptual Evaluation of Video Quality Standard in the preparation Based on the psychoacoustic properties of the human sense of hearing Based on the psycho visual properties of the human sense of sight PEDQ: Perceptual Evaluation of Data-Link Quality According to the standard ITU-T G.CHIRP

21 5. Dimensioning in a Triple-Play Area The 133% Dimensioning Rule BW needed must < BW available in the network. BW = (Min. BW for voice + Min. BW für audio + + Min. BW für video + Min. BW for data) ) x 1,33 The factor 1,33 takes care of the traffic management overheads. When deciding upon the minimum bandwidth per service, the number of clients assigned to each service must also be taken into consideration.

22 6. Conclusion and Future Work Triple Play services over IP have been a main topic of this presentation. Architectures for Triple Play services have been nor med. There are already several providers of services like Triple Play in the telecommunications market. An IP network is a very high-capacity transport platform. The last mile often proves to be a bottleneck; there is vast room for improvement here. Measurement of QoS in IP networks is necessary and is the only way to guarantee customer satisfaction. Suitable, inexpensive devices for measuring QoS are very important.

23 6. Conclusion and Future Work Search for alternative to the IP transport platform for Triple Play services Ethernet??! 1 Gigabit-Ethernet in Campus-Network (IEEE 802.3z) 10 Gigabit-Ethernet in Backbone-Network (IEEE 802.3ae) EPON in Access Area (IEEE 802.3ah) Priority (IEEE 802.1p/Q) Flow Control (IEEE 802.3x) OAM (IEEE 802.1ag; IEEE 802.3ah) Security (IEEE 802.1x/EAP; IEEE 802.1ae; IEEE 802.1af) Search for the equivalent to the E-Model (for Telephony) V -Model (for Video) Main, simple to measure network performance values are considered Simple, low costs, user kind performance tool

24 Theoretical and Practical Aspects of Triple Play Tadeus Uhl Thank you for your attention!