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Qos/CoS settings in DOCSIS 1.0 "show cable QoS profile"

Can somebody explain what different levels of priority (cable QOS profile refers

will mean for a cable modem against another with a lower level of prority when contending for bandwidth on their associated upstream? What does this command, and the level from 0 to 7, mean in real life as 1.0 is "best effort"? If the utlisation of that upstream is starting to to become overloaded will this prioritise data of one user over another?



Re: Qos/CoS settings in DOCSIS 1.0 "show cable QoS profile"

DOCSIS 1.0 defines the concept of a service identifier (SID), which specifies the devices allowed to transmit, provides device identification and CoS. In DOCSIS 1.0, each cable modem is assigned only one SID, creating a one-to-one correspondence between a cable modem and the SID. All traffic originating from, or destined for a cable modem is mapped to that cable modem's SID.

Typically, a DOCSIS 1.0 cable modem has one CoS and treats all traffic the same. Priority is one of the primary parameters available in Docsis 1.0 for QoS. Default priority value is 0. Given two SIDs with identical QoS parameters besides priority, the highest priority SID is given lower delay in servicing upstream bandwidth requests.

If a provider has many customers and want to give preference to traffic of some customers(cable modems) over others, the priority parameter can be used. When the request for bandwidth comes from these customers, the CMTS will service these requests on high priority basis compared to the request from other customers.

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