Specifying Downstream Queue Thresholds; Limiting Downstream Multicast Traffic - Motorola BSR 2000 Configuration And Management Manual

Release 1.0

Specifying Downstream Queue Thresholds

If the BSR is running both a time critical application (such as Voice Over IP) and best
effort service, the cable downstream threshold command guarantees that the
downstream scheduler can only release bandwidth within a certain specified range to
the downstream channel. When a higher priority VOIP packet arrives, the VOIP
packet will move ahead of the previously queued downstream non-VOIP data. This
command allows an operator to configure "back pressure" parameters for various
applications. Use the cable downstream threshold command, in Interface
Configuration mode, to specify downstream channel upper and lower queue
thresholds, as follows:
MOT (config-if)# cable downstream <NUM> threshold {bytes <500-65535>
<500-65535> | pdu <16-256> <16-256>}
where:

Limiting Downstream Multicast Traffic

The BSR can be configured to limit the amount of multicast traffic (including
DVMRP or PIM) on a downstream channel. Limiting the amount of multicast traffic
allows an MSO to balance the bandwidth requirements of IP-based video streaming
services with other bandwidth critical services such as voice traffic or high-priority
business traffic. Multicast traffic rate limiting is achieved by creating a static
multicast downstream service flow and assigning the service flow to a service class.
Use the cable multicast command, in Global Configuration mode, to create a static
multicast downstream service flow and assign the service flow to a service class, as
follows:
MOT:7A (config)# cable multicast <A.B.C.D> <A.B.C.D> [<WORD>]
where:
526360-001-00 Rev. B
NUM is the downstream channel number.
bytes uses the byte count as a threshold unit.
500-65535 specifies the upper byte threshold (default is 1000).
500-65535 specifies the lower byte threshold (default is 500).
pdu uses the PDU count as a threshold unit.
16-256 specifies the upper PDU threshold (default is 32).
16-256 specifies the lower PDU threshold (default is 16).
A.B.C.D is the destination IP multicast address.
MGBI
Configuring the CMTS
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