|
This is written for system SEIT level Systems Engineering, but is applicable when tailored (i.e., identify appropriate participants) for use in the segment level SE process also. Analysis 1. Assign Use Case to engineer for elaboration and analysis 2. Specify Source (driving) requirement(s) for Use Case (A-Spec) 3. Develop Data Flow Diagram (functional context diagram) 4. Develop Scenario Sequence Diagram (SSD) and associated Event Flow Table 5. Identify source requirements for each transaction (row) of EFT 6. Identify where derived (B-Spec) requirements are needed 7. Identify design assumptions, as required, for each transaction (row) of EFT 8. Include comments/concerns as required, for each transaction (row) of EFT 9. Schedule community review 10. Hold community review (Note; this is a non-trivial activity which should be allocated at least I day per use case) a. System Architect b. Use Case Model Owner c. System Model Owner d. System SEIT Conops team e. System SEIT I&T f. System SEll Requirements g. Segment representation 11. Make updates to analysis packages as required 12. Perform requirements audit (AP identified Use Case to B-Spec requirement) 13. Generate new derived requirements, as needed 14. Link requirement to AP in DOORS (create an A attribute in DOORS) 15. Prep for SFR a. Focus on High Risk requirements (requirements that are vague and have high potential for malicious interpretation with cost/schedule impact) b. Make and capture clarifying assumptions for each of above c. Insure APs are available in read file Post SFR System Engineering Design Document (SEDD) development 16. Merge approved/reviewed scenario into System model 17. Support configuration change process, as required, based on review The Analysis PackageThe Analysis Package is a structured engineering artifact that captures architecture and behavior and validates design against requirements. The typical structure of an Analysis Package is,… <Scenario
Name> Summary/Overview <Summarize the purpose/goal of the thread, including
the driving system level requirement fulfilled by the Thread. This should be one or two paragraphs > Preconditions <Describe the required
state of the system before the thread can begin including data required and
other threads that this one is dependent upon. A thread dependency diagram may be
useful.> Actors: <List of Operators or
Nodes involved in the Thread. Time is
often used as an actor. > Context Diagram: <Graphic depiction of
interfaces between actors. > Scenario Sequence
Diagram (SSD): <Graphic depiction of
sequential interactions between actors.
The message sequence chart illustrates the source and receiving actors
(operators or nodes), the interface message from the source to the receiver,
and the processing by the receiver.
See Example in Appendix> Event Flow Table <The Event Flow Table
describes the details of the MSC capturing for each event in the operation
sequence the requirement it satisfies.
The Event Flow Table includes (where applicable) derived requirements,
requirements clarifications, assumptions and other awareness derived from the
Thread exercise. > Post-Conditions <Describe the state of the system or product when the thread ends successfully> |