Motorola BSR 2000 Configuration And Management Manual page 264

BSR 2000 Configuration and Management Guide
6-78
The initial ranging start and end backoff values are a part of the Upstream
Bandwidth Allocation Map (MAP) that CMs use to register with the CMTS. If a
CM initial ranging request collides with requests from other CMs during the
initial ranging process, the CM initial ranging request is lost. The CMTS does not
directly detect the collision. The CM determines that a collision (or other
reception failure) occurred when the next MAP fails to include acknowledgement
of the request. The CM must then perform a back-off algorithm and retry its
initial ranging request causing prolonged CM downtime.
The initial ranging backoff start and end number of backoffs (wait times) can be
adjusted to randomize when initial ranging is initiated by CMs that are colliding
during initial ranging. This adjustment lowers the odds for CMs colliding again,
reducing the amount of time that a CM is down.
Use the cable upstream range-backoff command in Interface Configuration
mode to set the initial ranging backoff start and end time. If the automatic
argument is used, the CMTS automatically sets the upstream data-backoff start
and end values:
MOT(config-if)#cable upstream <NUM> range-backoff [automatic |
<0-15> | <0-15>]
where:
automatic prompts the ranging backoff to start and end automatically.
NUM is the upstream port number.
0-15 is the start ranging backoff number of requests.
0-15 is the end ranging backoff number of requests.
Use the no cable upstream range-backoff command in Interface Configuration
mode to return the range-backoff function to the default:
MOT(config-if)#no cable upstream <NUM> range-backoff [automatic |
<0-15> | <0-15>]
where:
automatic prompts the ranging backoff to start and end automatically.
NUM is the upstream port number.
0-15 is the start ranging backoff number of requests.
0-15 is the end ranging backoff number of requests.
MGBI
Release 1.0
526360-001-00 Rev. B