Voice Quality Measurement

1
Voice Quality Measurement

• Hyeongu Son
• hgson_at_cnu.ac.kr
• Data Networks Laboratory
• Computer Engineering
• Chungnam National University

2
Contents

• Introduction
• Propose
• Background Work
• Approach
• VoIP Quality Measurement
• Test Environment
• Future Test Environment
• Conclusion

3
Introduction

• Traffic Monitoring
• Check QoS(packet loss, delay, jitter, etc)
• Estimate network state
• VoIP
• Internet based
• Increasing user quickly
• Replacement of existing phone(PSTN)
• Mobility
• Cell phone, labtop computer

4
Purpose

• Previous research
• To provide QoS of VoIP traffic
• To measure QoS metrics such as delay, jitter,
  packet loss and throughput
• Current research
• To develop showing VoIP quality supporting IPFIX
  in IPv4 and IPv6 network
• In addition, support Mobile IPv6 environment

5
Background Work(1)

• VoIP traffic detection
• The method
• Detect SIP using 5060 port
• Obtain RTP session information such as source IP
  address / port and destination IP address /port
  from SIP/SDP
• Based on IPv4 wired environment
• QoS monitoring
• Measure delay, jitter, packet loss and throughput
• Measurement point
• Not end point
• Measured at router using IPFIX

6
Background Work(2)

• VoIP traffic flow
• Use Weongo Phone
• SIP based
• Data RTP based

7
Background Work(3)

• VoIP traffic detection result

• Bit rate

• Packet rate

32Kbps

• Average / Minimum delay

• Maximum delay

• Packet loss

• Jitter

8
Approach

• Key idea
• Use the network performance metrics of MIPv6
  environment
• One-way delay at router
• Packet loss rate at router
• VoIP quality anaiyzes by using two metrics of
  MIPv6 environment

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VoIP Quality Measurement (1)

• Voice quality analysis model (ITU-T G.107,
  E-model)
• Voice quality measurement as a computational
  model
• R Ro Is Id Ie_eff A
• R Transmission quality rating value
• Ro Signal-to-noise ratio
• Is Impairment factors that occur
  simultaneously with voice
• Received voice level, side tone, PCM
  quantization distortion
• Id Impairment factor that are delayed with
  respect to voice
• Use one-way delay
• Ie_eff Equipment impairment factors with
  packet loss
• Low bit rate voice codec, network packet loss
• A Advantage factor for new service

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VoIP Quality Measurement (2)

• Voice quality analysis model (ITU-T G.107)
• Voice quality measurement as a computational
  model
• R Ro Is Id Ie_eff A

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VoIP Quality Measurement (3)

• Target Voice traffic
• Generate this traffic using ITU-T G.711 codec
• G.711 (CBR VoIP traffic)
• support 64Kbps
• 20ms packetization interval
• Payload size 160 bytes
• Packet loss rate
• Use sequence number from RTP header
• One-way delay
• End-to-end measure Round Trip Time(RTT)
• One-way delay RTT/2
• Router unclearness

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Test Environment(1)

• Testbed composition
• 1 IPv6 router
• 4 mobile IPv6 access router
• 1 mobile node
• Access router
• Use general computer
• Four 3com wireless interface card
• Driver madwifi
• Configuration type of interface card
• AP mode 1, adhoc mode 2, monitor mode 3
• Configuration adhoc routing
• OLSR(Optimized Link State Routing)

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Test Environment(2)
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Future Testbed Environment
KOREN IPv6 Network
CNU IPv6 Router
tunneling
MIPv6 HA OLSR
channel
40
44
36
Fourth floor
36
40
Third floor
44
36
40
44
44
40
MIPv6 MN
36
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Conclusion

• VoIP quality measurement
• Use E-model(ITU-T G.107)
• Packetization use G.711 codec
• Generate CBR VoIP traffic
• Necessary metrics one-way delay, packet loss
  rate
• Future Work
• Find out method of measuring one-way delay at
  router
• After that, be able to measure VoIP quality at
  router
• Measure VoIP traffic quality through real
  distance at mobile IPv6 environment

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Reference

• 1 J. Quittek, T. Zseby, B. Claise, and S.
  Zander, Requirements for IP Flow Information
  Export (IPFIX), IETF RFC3917, Oct. 2004.
• 2 D. Johnson, C. Perkins, and J. Arkko,
  Mobility Support in IPv6, IETF
• RFC3775, June 2004.
• 3 Weongo phone, http//www.wengophone.com
• 4 J. Rosenberg and oth., RFC 3261, SIP
  Session Initiation Protocol,
• http//rfc.net/rfc3261.html, July 2003.
• 5 H. Schulzrinne and oth., RFC 3550, RTP A
  Transport Protocol for
• Real-Time Applications, http//rfc.net/rfc35
  50.html , June 2002.
• 6 ITU-T Recommandation G.107, The E-model, a
  computational model
• for use in transmission planning,
  http//www.itu.org , March 2003.
• 7 ITU-T Recommandation G.711, Pulse code
  modulation(PCM) of voice frequencies,
  http//www.itu.org , November 1988.
• 8 Madwifi http//madwifi.org/
• 9 OLSR http//www.olsr.org/

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• Thank you
• Do you have any question?