Rec. ITU-T E.220 (10/1992) … INTERCONNECTION OF PUBLIC LAND MOBILE NETWORKS (PLMN)
FOREWORD
1 Introduction
2 Scope
3 Related Recommendations
4 General principles of interconnection
5 Network interconnection scenarios
6 Echo control
    6.1 General
    6.2 Location of echo control devices
    6.3 Network control
    6.4 Implementation considerations
7 Roaming
8 Handover
9 History
ANNEX A … Alphabetical list of abbreviations used in this Recommendation