193CPE status and performance monitoringAn ACS can monitor the parameters of a CPE connected to it. Different CPEs have different performancesand functionalities. Therefore the ACS must be able to identify each type of CPE and monitor the currentconfiguration and configuration changes of each CPE. CWMP also allows the administrator to definemonitor parameters and get the parameter values through an ACS, so as to get the CPE status andstatistics information.The status and performance that can be monitored by an ACS include:• Manufacture name (Manufacturer)• ManufacturerOUI• SerialNumber• HardwareVersion• SoftwareVersion• DeviceStatus• UpTime• Configuration file (ConfigFile)• ACS address (URL)• ACS username (Username)• ACS password (Password)• PeriodicInformEnable• PeriodicInformInterval• PeriodicInformTime• CPE address (ConnectionRequestURL)• CPE username (ConnectionRequestUsername)• CPE password (ConnectionRequestPassword)CWMP mechanismAuto-connection between the ACS and a CPEWhen a CPE starts up for the first time, it automatically obtains an IP address from the DHCP server,which informs the CPE of the following information:• The URL address of the ACS (assigned by the DHCP server through Option 43)• Username and password for connecting the ACS (assigned by the DHCP server through Option 43)• DNS server address (directly assigned)After the CPE receives the above information, it has the IP address of the ACS resolved by the DNS server,and sends a connection request to the ACS. If the CPE passes the authentication with the acquiredusername and password, the connection between the ACS and the CPE is established.If the current session is not finished but the connection between ACS and CPE is interrupted, the CPEautomatically establishes a new connection with the ACS until the number of CPE auto-connection retriesreaches the limit.
