GSM 09.02 - Version 5.3.0 - Digital cellular telecommunications - ETSI

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GSM 09.02 Version 5.3.0: August 1996
15 General on MAP user procedures
15.1 Introduction
Clauses 15 to 21 describe the use of MAP services for GSM signalling procedures. GSM signalling
procedures may involve one or several interfaces running one or several application protocols. This ETS
addresses only the signalling procedures which require at least the use of one MAP service.
When a signalling procedure takes place in the network, an application process invocation is created in
each system component involved. Part of the application process invocation acts as a MAP user and
handles one or several MAP dialogues. For each dialogue it employs an instance of the MAP service
provider. It may also use other communication services to exchange information on other interfaces, but
detailed description of these aspects is outside the scope of this ETS.
15.2 Common aspects of user procedure descriptions
15.2.1 General conventions
For each signalling procedure this ETS provides a brief textual overview accompanied by a flow diagram
which represent the functional interactions between system components. Functional interactions are
labelled using the MAP service name when the interaction results from a service request or by this service
name followed by the symbol "ack" when this interaction results from a service response.
For each of the system components involved, this ETS also provides a detailed textual description of the
application process behaviour as well as an SDL diagram. SDL diagrams describe the sequence of events,
as seen by the MAP-User, which occurs at MAP service provider boundaries as well as external events
which occur at other interfaces and which impact on the previous sequence.
External events do not necessarily correspond to the messages of other protocols used in the system
component. The MAP-user procedures are described as if a set of interworking functions (IWF) between
the MAP-user and the other protocol entities was implemented (see figure 15.2/1). Such interworking
functions are assumed to perform either an identity mapping or some processing or translation as required
to eliminate information irrelevant to the MAP-user.
The mapping of service primitives on to protocol elements is described in clauses 11 to 14.
GSM signalling procedures are built from one or more sub-procedures (e.g. authentication, ciphering, ....).
Sub-procedures from which signalling procedures are built are represented using SDL MACRO
descriptions.
In case of any discrepancy between the textual descriptions and the SDL descriptions, the latter take
precedence.
15.2.2 Naming conventions
Events related to MAP are represented by MAP service primitives. The signal names used in the SDL
diagrams are derived from the service primitive names defined in clauses 5 to 10, with some lexical
transformations for readability and parsability purposes (blanks between words are replaced by
underscores, the first letter of each word is capitalized).
Events received and sent on other interfaces are named by appending the message or signal name to a
symbol representing the interface type, with some lexical transformations for readability and parsability
purposes (blanks between words are replaced by underscores, the first letter of each word is capitalized).