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One Model, Many Interests, Many Views
Ports reflect additional design details reflecting how connections connect to the parts. Ports are drawn
as squares on the boundary of the part, can be nested within other ports, and can be labeled with
their own name reflecting identity. Ports have arrows reflecting directionality of flow (in, out, or inout).
Ports optionally display ball and socket style decorations reflecting provided interfaces (drawn as balls
connected to the port) and required interfaces (drawn as sockets).
Internal block diagrams have a much higher level of detail than a classic physical or interface block
diagram. This detail and the corresponding notations make IBDs ideal for detailed design specification
of logical or physical connectivity when communicated to system engineers, software engineers, and
subject matter experts. This same level of detail can become problematic at higher levels of abstraction
and with broader audiences. In those cases, it is often best to leverage the block diagram with its
similar content and structure at an architectural level.
Interface and Physical N 2 Diagrams
Though infrequently used, interface and physical N
2
diagrams leverage the same concepts of the
functional N
2
diagram to represent interfaces and physical connections within a system or system
segment. These variants of the N
2
diagram present a simplified representation of connectivity between
parts. What these diagrams lack in technical detail (and style) of various block diagram representations,
they deliver in simplicity and clarity.
Level of Detail:
Low
Audience:
General
Content:
Single-level composition
with corresponding logical
(interface) or physical (link)
connections
Use:
Identification of connections;
clustering analysis