Hyungsoo Kim

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Performance Objectives for performance testing on
CJK NGN testbed

• Hyungsoo Kim
• (hans9_at_kt.co.kr)

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Contents

• Why?
• Problem statements
• Study plan
• Further consideration

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1. Why?

• The purpose of performance testing (Scenario 6)
  is to evaluate a service would be achieved the
  required performance level.
• The required performance level (objectives)
  should be identified.
• Some performance parameters have been discussed
  in Testbed Group delay, delay variation, loss,
  etc.
• ITU-T Recommendations could be referred.
• i.e., Y.1541 (Network performance objectives
  for IP-based services)

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2. Problem statements

• Table of Y.1541 refers to Service Level
  Requirements, independent of actual distance and
  number of links.
• At least 2 references are existing TTC TTA
  for VoIP service requirements
• End-to-end delay of Class A (TTC) 100 ms
• End-to-end delay (TTA) 150 ms
• If the path under test covers from Seoul, Korea
  to Tokyo, Japan, and the performance testing
  result shows around 200 ms (90 ms of Japan side
  110 ms of Korea side), is it good quality ?
• Y.1541 QoS class 0,2 6 lt 200ms lt TTC class C
• CJK NGN testbed will cover the distance from
  Japan to China through Korea.
• (currently, from China to Korea)
• A note of Table 1 of Y.1541 introduces as
  follows
• In some other circumstances (i.e., longer than
  5000 km distance), the IPTD objectives in Classes
  0, 2 and 6 will not always be achievable.

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3. Study Plan

• Allocation rules of ITU-T Recommendation Y.1542
  could be referred for this purpose - Framework
  for achieving end-to-end IP performance
  objectives
• Y.1542 recommends quite many approaches
• - Static
• - Pseudo-static
• - Signaled
• - Impairment accumulation

Which approach should be applied?

• The study considers various approaches toward
  achieving end-to-end (UNI-UNI) IP network
  performance objectives.
• ? Analysis and choice of approaches pros and
  cons
• ? Identification of distance for an end-to-end
  test path on CJK NGN testbed
• ? Calculation of actual performance objectives
  for performance testing on CJK NGN testbed

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4. Further considerations

• The real environment of CJK NGN testbed should
  be recognized.
• Relationship with national requirements in each
  countries policy should be taken into account.
• Cooperation and coordination among 3 countries
  organizations (TTC, CCSA and TTA) is needed.
• The international VoIP service requirements
  (i.e., service license) may be considered.
• Performance allocation among providers on
  nation-wide may be studied.