computer architecture (computer science) the structure and organization of a computer's hardware or system software; "the architecture of a computer's system software"
specification -
(patent law) a document drawn up by the applicant for a patent of invention that provides an explicit and detailed description of the nature and use of an invention
restriction,
confinement the act of keeping something within specified bounds (by force if necessary); "the restriction of the infection to a focal area"
specification A document that prescribes, in a complete, precise, verifiable manner, the requirements, design, behavior, or characteristics of a system or system component. (source IEEE)