• A system is a collection of components organized to accomplish a specific function or set of functions.
• The architecture of a system is the system's fundamental organization, embodied in its components, their relationships to each other and to the environment, and the principles guiding it design and evolution.
• An architecture description is a collection of artifacts that document an architecture.
• Stakeholders are people who have key roles in, or concerns about, the system: for example, as users, developers, or managers. Different stakeholders with different roles in the system will have different concerns. Stakeholders can be individuals, teams, or organizations (or classes thereof).
• Concerns are the key interests that are crucially important to the stakeholders in the system, and determine the acceptability of the system. Concerns may pertain to any aspect of the system functioning, development, or operation, including considerations such as performance, reliability, security, distribution, and evolvability.
• A view is a representation of the whole system architecture; the architect creates one or more architecture models, possibly using different tools. A view will comprise selected parts of one or more models, chosen so as to demonstrate to a particular stakeholder or group of stakeholders that their concerns are being adequately addressed in the design of system architecture.
• A viewpoint defines the perspective from which a view is taken.

This is a good presentation covering IEEE 1471

IEEE 1471 is a great set of definitions for Architectural Principles but does not define Infrastructure Archiecture as an area.

Thanks for the email Jon