This attribute represents the CMTS upstream filtering status for this CM. The value 'true' indicates that the CMTS has sent UDCs to the CM during registration process. In order for a CMTS to send UDCs to a CM, the CMTS MAC Domain needed to be enabled via the MAC Domain attribute SendUdcRulesEnabled and the CM had indicated the UDC capability support during the registration process. The value 'false' indicates that the CMTS was not enabled to sent UDCs to the CMs in the MAC Domain, or the CM does not advertised UDC support in its capabilities encodings, or both. Since the CMTS capability to sent UDCs to CMs during the registration process is optional, the CMTS is not required to implement the value 'true'.