ITU-T Rec. E.152 � INTERNATIONAL FREEPHONE SERVICE (IFS)
1 Preamble
2 Definition
    2.1 Possible applications
3 Management
    3.1 Service ordering
    3.2 Operating practices
    3.3 Data collection
4 Customer's features
    4.1 Universal freephone number
    4.2 Announcement for callers
    4.3 Geographical zone call routing
    4.4 Time-dependent call routing
    4.5 Call completion on busy (traffic-dependent) call routing
    4.6 Subscriber statistics
    4.7 Directory assistance/listing service
5 Operational and technical provisions
    5.1 General description
    5.2 Operational requirements
    5.3 Technical requirements
    5.4 Network management
6 Quality of service
ANNEX A
ANNEX B
ANNEX C