Step 4—Interpret the MAC Log File and Take Action
Troubleshooting Tips for the Cisco uBR924 Cable Access Router 17
Event 8—Transfer Operational Parameters
After the DHCP and security operations are successful, the Cisco uBR924 downloads operational
parameters via a configuration file located on the cable company’s TFTP server. The
CMAC_LOG_DHCP_CONFIG_FILE_NAME field shows the filename containing the transmission
parameters.
508177.164 CMAC_LOG_STATE_CHANGE configuration_file_state
508177.166 CMAC_LOG_LOADING_CONFIG_FILE platinum.cm
508178.280 CMAC_LOG_CONFIG_FILE_PROCESS_COMPLETE
Event 9—Perform Registration
After the Cisco uBR924 is initialized, authenticated, and configured, it requests to be registered with
the headend CMTS. The CMAC_LOG_COS_ASSIGNED_SID field assigns a class of service (CoS)
number and a service ID (SID). Multiple CoS entries in the configuration file imply that multiple
SIDs are supported by the cable access router. If several cable access routers use the same
configuration file, they will have the same CoS numbers but will be assigned different SIDs.
A successful registration is indicated by the CMAC_LOG_REGISTRATION_OK field.
508178.300 CMAC_LOG_STATE_CHANGE registration_state
508178.302 CMAC_LOG_REG_REQ_MSG_QUEUED
508178.306 CMAC_LOG_REG_REQ_TRANSMITTED
508178.310 CMAC_LOG_REG_RSP_MSG_RCVD
508178.312 CMAC_LOG_COS_ASSIGNED_SID 5/19
508178.314 CMAC_LOG_COS_ASSIGNED_SID 6/20
508178.316 CMAC_LOG_COS_ASSIGNED_SID 7/21
508178.318 CMAC_LOG_RNG_REQ_QUEUED 19
508178.320 CMAC_LOG_REGISTRATION_OK
Event 10—Comply with Baseline Privacy
Keys for baseline privacy are exchanged between the Cisco uBR924 and the headend CMTS. During
this event, a link level encryption is performed so that a user’s data cannot be “sniffed” by anyone
else who is on the cable network.
Following is a trace that shows baseline privacy enabled. The key management protocol is
responsible for exchanging two types of keys: KEKs and TEKs. The KEK (key exchange key, also
referred to as the authorization key) is used by the headend CMTS to encrypt the TEKs (traffic
encryption keys) it sends to the Cisco uBR924. The TEKs are used to encrypt/decrypt the data. There
is a TEK for each SID that is configured to use privacy.
851.088 CMAC_LOG_STATE_CHANGE establish_privacy_state
851.094 CMAC_LOG_PRIVACY_FSM_STATE_CHANGE machine: KEK, event/state:
EVENT_1_PROVISIONED/STATE_A_START, new state: STATE_B_AUTH_WAIT
851.102 CMAC_LOG_BPKM_REQ_TRANSMITTED
851.116 CMAC_LOG_BPKM_RSP_MSG_RCVD
851.120 CMAC_LOG_PRIVACY_FSM_STATE_CHANGE machine: KEK, event/state:
EVENT_3_AUTH_REPLY/STATE_B_AUTH_WAIT, new state: STATE_C_AUTHORIZED
856.208 CMAC_LOG_PRIVACY_FSM_STATE_CHANGE machine: TEK, event/state:
EVENT_2_AUTHORIZED/STATE_A_START, new state: STATE_B_OP_WAIT
856.220 CMAC_LOG_BPKM_REQ_TRANSMITTED
856.224 CMAC_LOG_BPKM_RSP_MSG_RCVD
856.230 CMAC_LOG_PRIVACY_FSM_STATE_CHANGE machine: TEK, event/state:
EVENT_8_KEY_REPLY/STATE_B_OP_WAIT, new state: STATE_D_OPERATIONAL
856.326 CMAC_LOG_PRIVACY_INSTALLED_KEY_FOR_SID 2
856.330 CMAC_LOG_PRIVACY_ESTABLISHED
Note In order for baseline privacy to work, you must use a code image name on the CiscouBR924
that contains the characters k1. In addition, baseline privacy must be supported on the headend
CMTS, and it must be turned on in the configuration file that is downloaded to the Cisco uBR924.