vals, which is done without polling of the CMs by the CMTS. This type is convenient for traffic with constant bitrate such as voice traffic. Unsolicited grant with activity detection. This is a reservation-based resource manage- ment which is in fact a hybrid of the polling and unsolicited grant scheduling types. Here CMTS provides CMs with fixed grants at nearly fixed time intervals as long as data is queued for transmission in the upstream. While the CM is non-active, the schedulers go into the polling mode of operation. In the downstream direction (from CMTS toward the CMs), service flows are defined with the same QoS parameters that are used for the best-effort scheme in the upstream direction. For all scheduling types, all dynamic service flows may be in one of the three logical states: authorized state (network policy rules are applied, resulting in an authoriza- tion), admitted state (resources are reserved by the scheduler for inactive service flows, which assures that subsequent activation requests will succeed), and active state (here the service flow is already activated and QoS-marked packets can traverse). Speaking literally, one should note that DOCSIS in fact does not define states, but they are log- ically constructed to describe the resource management (i.e. QoS management) which is performed by the CMTS for the cable data traffic. Optionally, DOCSIS 3.1 provides hierarchical QoS (HQoS) [17]. The HQoS aims to provide an intermediate level in the scheduling hierarchy between service flows on one side (upper protocol side) and physical channels (in the cables) on the other side, by introducing aggregate traffic QoS treatment (via aggregated service flows - ASFs). There are two options for HQoS (for implementations). One is to provide aggregation of unicast service flows which are associated with a single CM, and the second option is to aggregate service flows coming from multiple CMs but sharing the same cable toward 4 QoS for Fixed Ultra-Broadband the CMTS. In this manner, the HQoS enables telecom