CONTENTS

�1���� General
�2���� General design objectives
������� 2.1���� Exchange modifications and growth
������� 2.2���� Service provisioning and records
������� 2.3���� Translations and routing information
������� 2.4���� Resource utilization
������� 2.5���� Physical design objectives
�3���� Integrated Digital Network design objectives
������� 3.1���� Exchange timing distribution
������� 3.2���� Network synchronization
������� 3.3���� Slip��
������� 3.5���� Synchronization requirements when interworking with a digital satellite system
�4���� Availability design objectives
������� 4.1���� General
������� 4.2���� Causes of unavailability
������� 4.3���� Intrinsic and operational unavailability
������� 4.4���� Planned outages
������� 4.5���� Total and partial unavailability
������� 4.6���� Statistical basis
������� 4.7���� Relevant failure events
������� 4.8���� Availability independence
������� 4.9���� Intrinsic downtime and unavailability objectives
������ 4.10���� Operational unavailability objectives
���� ��4.11���� Initial exchange availability performance
�5���� Hardware reliability design objectives