2.9.5 Internal Security and External Security
Internal and external security is another view of protecting the data and the communications in the system.
Internal security is the means by which the system protects its own data and internal communications, and external security is the means by which the system protects external communications. For the system, application messages are external communications. Objects described in section 2.9.1are internal data. For communications labeled in the figure captioned "Component storage and communications" in section 2.9.1, 1 is internal communication, and 2, 3, and 4 are external communications.
The security mechanisms previously described are used to ensure both internal and external security.