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• ITU-T Rec. Q.725 (1988)
• 1 Introduction
• 2 Unsuccessful calls due to signalling malfunction
• 3 Unavailability of a signalling route set
• 4 Labelling potential
• 5 Cross-office transfer time
  • 5.1 Functional reference points and transfer time components
  • 5.2 Definitions
  • 5.3 Queueing delay
  • 5.4 Estimates for message transfer time
  • 5.5 Effect of retransmission
• References