This clause describes the template used in developing information flow (IF) procedures.
"Name of procedure (e.g. Terminal location registration)"
In this clause, provide a brief prose description of the service or network capability. The "X.Y.Z."
refers to the clause heading number.
This clause consists of subparagraphs each dedicated to one information flow of the IF diagram. For each information flow, a detailed description is provided on the information flow name, certain information elements (IEs) within the information flow, whether the IE is mandatory or optional (M/O), in the sequence as shown in the IF diagram. FE actions (FEA) are also provided in this clause. This clause format is proposed as follows:
Initial information flow: One should normally describe the initiating FE Action (FEA) leading to the first flow. Any information that is specifically required to support the operation should be mentioned (e.g. this flow conveys the user identity to the HSS).
Each paragraph should contain a brief description of the flow and any specific start and end FEAs. When information to be conveyed is optional, the conditions for its inclusion should be specified and the response to its presence when received should also be specified (e.g. Include IP Address when condition xyz occurs). For an information flow that is required, the description should indicate whether a response is required based on successful outcome to the received IF, failed outcome, both or neither. e.g. "Response is required indicating Success or Failure".
Flows may occur in either direction but not both at the same time. To indicate a shorthand for multiple flows, use a procedure box as in flow 5 or 6.
Flows that are an optional part of the procedure should be shown as dotted arrows as in flow 4. These may appear in either direction.
A set of flows, representing a common procedure, is shown by a box. The procedure should be numbered and named with a name that corresponds to the procedure as described elsewhere. The location of the box on an entity represents the start of the common procedure regardless of the number of the entities involved in the procedure.
An optional set of flows is represented as a dashed box. Otherwise the use is the same as in flow 5.
A small number of alternative flows may be shown within a dashed box. The alternatives are shown by a letter immediately following the flow number, e.g. 7a, 7b, 7c, etc. Where a single alternative results in multiple flows, they must be shown with an indication of the proper sequence, e.g. 7b1, 7b2. The subparagraph describing the information flow must describe the decision process taken in choice of alternatives.
Alternative (a) is described. If alternative (a) is a single information flow, the contents and purpose of that information flow is included here.
Alternative (b) is described.
The first information flow of alternative (b) is described
The second information flow of alternative (b) is described. Etc.
The final flow in a procedure may provide additional information regarding other procedures that might follow it but such information is not required.
The general characteristics of the information flow template are as follows:
All relevant functional entities are contained in the flow diagram. Only relevant entities need be shown.
When an element occurs only in an information flows for which several alternatives exist, the description box for the functional entity and the vertical line shall be dashed lines.
The specific network affiliation of functional entities may be shown using a labelled bracket over the specific entities as shown in the Figure (e.g. Home Network). Such labelling is not required unless the flow would not be clear without it.
The number associated with each flow provides a "handle" to the functional entity action (FEA) executed by the FE receiving the flow. This number is known only within the scope of the specific information flow diagram. The description of this functional entity action (FEA) immediately follows the information flow description.
Common Procedures described elsewhere can be used in the information flows in order to simplify the diagram. These may be either required or optional.
Each common procedure is treated as a single action and therefore is given a unique number.
An optional flows (flows 4 and 6) are indicated by a dashed arrow or box.
Co-ordinated flows or flows that illustrate parallel actions are indicated by the flow text description. For example one might see a description such as: "flows 5 and 6 may be initiated any time after flow 3".
Sequential operation is assumed unless indicated otherwise.