### Question
How is the "modular system interface" defined?


### Answer
The term **modular system interface** is defined in *10 U.S.C. § 4401* as follows -

> a shared boundary between major systems, major system components, or modular systems, defined by various physical, logical, and functional characteristics, such as electrical, mechanical, fluidic, optical, radio frequency, data, networking, or software elements

#### Citation:
  - *10 U.S.C. § 4401*
  - Heading: **Subtitle A-General Military Law > PART V-ACQUISITION > Subpart F-Major Systems, Major Defense Acquisition Programs, and Weapon Systems Development > CHAPTER 327-WEAPON SYSTEMS DEVELOPMENT AND RELATED MATTERS > SUBCHAPTER I-MODULAR OPEN SYSTEM APPROACH IN DEVELOPMENT OF WEAPON SYSTEMS**

