Upstream resource reservation and scheduling strategies for hybrid fiber/coaxial networks

Providing QoS guarantees in HFC networks is a very important and challenging problem. In this paper we discuss the design of the upstream scheduler both at the station (cable modem) and the head-end (H/E) controller. Due to the large round-trip transmission delay, and the possibility of having contention while transmitting in the upstream channel, the design of an upstream scheduler should tie up closely with the upstream resource reservation scheme. Our contributions are two fold. Firstly, we propose several upstream resource reservation strategies that can support different levels of QoS guarantees, namely the deterministic guaranteed (DG) service, the statistical guaranteed (SG) service, the best effort with minimum guaranteed (BEMG) service, and the best effort (BE) service. Secondly, we discuss some possible upstream scheduling strategies that can be used in designing the upstream scheduler and present our proposed distributed hybrid scheduling strategy.