MODERNIZING THE CABLE SERVICE DELIVERY INFRASTRUCTURE
Market forces and the insatiable demand for bandwidth, both upstream and downstream, are driving cable operators to modernize their network infrastructure and operations. Many technologies and operational improvements are available to them in the short and longer term to support this end.Operators today are increasing the average capacity per subscriber by reducing the size of their service groups whenever they pull fiber closer to the subscriber. Operators are also expanding the total capacity offered within their networks by increasing the width of the useable RF spectrum inside their HFC plants. In addition, they are looking to replace analog fiber with digital fiber for better transmission characteristics and better reliability. Some operators are also planning to consolidate their headends and hubs to reduce operational complexity and cost. At the same time, technological innovation is providing new directions, of which some of the most impactful are the Distributed Access Architecture (DAA), Virtualization, Full Duplex DOCSIS, and Extended Spectrum DOCSIS.
The DAA presents two options: moving the PHY layer to the node in the access network (Remote PHY or R-PHY or RPD) or moving both the PHY and MAC to the node (Remove MACPHY or R-MACPHY or RMD). Each option has advantages and tradeoffs.