Bandwidth admission control mechanism for supporting QoS over DOCSIS 1.1 HFC networks

In order to support quality of service (QoS) for real-time data, such as voice over IP (VoIP), video on demand (VoD) and other multimedia services, HFC (hybrid fiber coax) networks must provide an effective priority scheme. Data over cable service interface specifications v1.1 (DOCSIS 1.1), developed for data transmission over the HFC networks, defines five upstream services to support per-flow QoS. However, it does not define how to schedule these upstream services. We propose a new bandwidth admission control mechanism to support QoS in DOCSIS 1.1 HFC networks. In our scheme, the five upstream services are classified into two services - periodic services and aperiodic services. The periodic services are time-sensitive services, and they must provide bandwidth and access delay guarantee. The proposed admission control mechanism can satisfy them. The analysis and simulation results confirm that the throughput and delay are better than several proposed schemes.