L2 — Logical Structure

Purpose & Usage

The L2 Viewpoint is concerned with identifying of how nodes are structured and their dependencies to other nodes through the use of Needlines for a relevant logical scenario.

• User Requirements.
• Operational Planning.
• Scenario Specification.
• Definition of operational concepts.
• Definition of collaboration needs.
• Problem space definition.
• Supply chain analysis.

Scope

• Shall contain Nodes relevant for the entity of interest and their structural organization.
• Shall contain Needlines between Nodes.
• May show Logical Passive Resources that the Needlines convey.

Representation

• Topological (connected shapes).
• Composite structure diagram.
• Rich Picture.

Cut-out (Meta-model)

flowchart TB
    Node:::activity
    Needline:::activity
    LPR["Logical Passive Resource"]:::activity
    Node -->|"Needline (aggregates)"| Node
    Needline -->|"is equal to"| Node
    Needline -->|"conveys"| LPR
    classDef activity fill:#9DC3E6,stroke:#1F4E79,color:#000

Notes on the Cut-out

A Needline expresses a need statement for key and/or aggregated exchanges of conveyed Items by a Node, prior to its distinction into types of Node in this view. It is similar to an objectified relation where the element represents the instantiated form of a connection.

NAFv4 Compliant Example

flowchart LR
    Search["«Node» Search"]:::activity
    AssetControl["«Node» Asset Control"]:::activity
    Rescue["«Node» Rescue"]:::activity
    TacticalC2["«Node» Tactical C2"]:::activity
    Search -->|"control"| AssetControl
    Search -->|"status"| Rescue
    AssetControl -->|"tasking"| Rescue
    AssetControl -->|"control"| TacticalC2
    TacticalC2 -->|"rescue"| Rescue
    TacticalC2 -->|"tasking"| Search
    classDef activity fill:#9DC3E6,stroke:#1F4E79,color:#000