The Data Over Cable Service Interface Specifications (DOCSIS) is intended to support IP flows over HFC (Hybrid Fiber/Coax) networks with significantly higher data rates than analog modems and Integrated Service Digital Network (ISDN) links for high quality audio, video and interactive services. To support quality-of-service (QoS) for such applications, it is important for HFC networks to provide effective media access and traffic scheduling mechanisms. In this paper, we first present a multilevel priority collision resolution scheme with adaptive contention window adjustment. The proposed collision resolution scheme separates and resolves collisions for different traffic priority classes (such as delay-sensitive and best effort streams), thus achieving the capability for preemptive priorities. Second, a novel MAC (media access control) scheduling mechanism and a new bandwidth allocation scheme are proposed to support multimedia traffic over DOCSIS-compliant cable networks. It is shown through simulation results that throughput and delay performance have been unproved for the transmission of real-time VBR (variable bit rate) traffic as compared to current DOCSIS specifications.
All Science Journal Classification (ASJC) codes
- Media Technology
- Electrical and Electronic Engineering