�1���� User-to-User Signalling (UUS)
������� 1.1���� Scope
������� 1.2���� References
������� 1.3���� Definitions
������� 1.4���� Symbols and abbreviations
������� 1.5���� Description
������� 1.6���� Derivation of the functional model
������� 1.7���� Information flows
������� 1.8���� SDL diagrams for functional entities
������� 1.9���� Functional entity actions (FEAs)
������ 1.10���� Allocation of functional entities to physical locations