CONTENTS

�1���� Definitions
������� 1.1���� essential information (of internal automatic observations)
������� 1.2���� supplementary information (of internal automatic observations)
������� 1.3���� Answer Seizure Ratio (ASR)
������� 1.4���� Answer Bid Ratio (ABR)
������� 1.5���� Network Effectiveness Ratio (NER)
�2���� Merits of internal automatic observations
�3���� Time of observations
�4���� Exchange of the results of observations
�5���� Classes of calls
�6���� Destination analysis from service observation data
�7���� Details about supplementary information for Signalling System No. 5
������� 7.1���� Signalling faults
������� 7.2���� Ineffective calls associated with the calling subscriber
������� 7.3���� Ineffective calls associated with the called subscriber
������� 7.4���� Network
�8���� Equipment impact
Annex A - Cause value categorization