DOCSIS-CMTS-CM-REG-STATUS is an IPDR Service Definition Schema that defines the Registration status of the CM as perceived by the CMTS. Revision History: 3.5.1-A.1: Initial version. 3.5.1-A.2: Revised version includes ECN OSSIv3.0-N-12.1073-3 and published as I20. 3.5.1-A.3: Revised version includes ECN OSSIv3.0-N-12.1083 and published as I21. 3.5.1-B.1: Revised to include DOCSIS 3.1 elements. 3.5.1-B.2: Revised version includes ECN CCAP-OSSIv3.1-N-20.2119-1. DOCSIS 3.1 CCAP Operations Support System Interface Specification CCAP-OSSIv3.1-N-15.1390-1 The IPDR Record containing one CM registration status instance representing a single cable modem that has registered with the CMTS.