DOCSIS 3.0 CM Control
DOCSIS 3.0 CM Control Request:
The CM-CTRL-REQ command is used to enforce specific CM actions. It is a replacement to the DOCSIS 2.0 UPDIS
management message. The CMTS MUST support the CM-CTRL-REQ message. The CM MUST support the
CM-CTRL-REQ message.
A CMTS MUST generate the CM-CTRL-REQ message.
The CM MUST accept a CM-CTRL-REQ message on any available downstream.
1: Upstream Channel RF Mute
This field contains the Channel ID of the upstream to mute or un-mute. A value of 0 will mute or unmute
all channels.
The mute operation is a low level disabling of the physical layer transmitter that is currently using the
channel ID. It will not directly change the MAC layer state, although if the mute period is long
enough the MAC layer will experience T4 timeout as if the channel has become physically
unavailable.
If all channels are muted and the CM encounters a condition which leads it to the Re-Init MAC
state, the CM MUST defer re-initialization and remain muted until the mute timer expires, an unmute
command is received, or a Lost SYNC event occurs, at which point it performs a re-init MAC
and is no longer muted.
2: RF Mute Timeout Interval
For the RF Mute operation, this field controls the length of time that the upstream channel(s) are
muted. This field is a 32-bit unsigned integer in units of milliseconds. The CMTS MUST include the
RF Mute Timeout Interval TLV when the Upstream Channel RF Mute TLV is included in the CMCTRL-
REQ message.
A timeout of 0x00000000 is an indication to un-mute the channel(s) immediately.
A timeout of 0xFFFFFFFF is an indication to mute the channel(s) indefinitely.
3: CM Reinitialize
A value of 1 instructs the CM to reinitialize its MAC with a CM Initialization Reason of
CM_CTRL_INIT and will begin a new registration process.
Any value other than 1 is ignored.
4: Disable Forwarding
A value of 1 will disable forwarding of data PDUs in both the upstream and downstream direction.
A value of 0 will enable forwarding of data PDUs in both the upstream and downstream direction.
Any value other than 0 or 1 will be ignored.