This read-write boolean sets the default value applied to docsSubMgtCpeControlActive when DOCSIS registration doesn't explicitly signal a value, and it persists across device resets. Operators use it to decide whether subscriber management filtering is on by default across the system for modems that don't specify otherwise. For example, the DEFVAL of false means new modems registering without an explicit setting will not have CMTS-based CPE control active by default.