Part 2 – Network Convergence – Distributed Access Architectures
Created November 6, 2019
Guest BlogSCTE Cable-Tec EXPO 2019 is now behind us and ProLabs was busy with a number of new product announcements tailored to Multiple System Operator (MSO) and Cable TV operators’ distributed access architecture (DAA) networks. SCTE 2019 continued the industry’s focus on Remote PHY and other DAA and the consensus across the event is that after years of discussion and a few trials, DAA will take a quantum leap forward in 2020.
The DAA migration will radically transform MSO networks. Analog hybrid-fiber coax (HFC) deployments will be upgraded to digital Ethernet-based networks that push the analog to digital conversion out of the headend to the outside plant. Analog lasers and RF splitters/combiners in the headends and hubs will be replaced with standard Ethernet switching and Dense Wavelength Division Multiplexing (DWDM) gear in order to reclaim and repurpose the existing fiber infrastructure to support more outside plant nodes that serve fewer customers. This network transformation will increase customer bandwidth to each node to 10Gbps, while reducing the power and footprint of hub and headend sites. Digitising the network from the node reduces the costs of managing concurrent analog and digital services.
ProLabs has led the conversation about overcoming the practical challenges of deploying DAA for some time. Initial challenges only dealt with technology limitations. Deploying Wavelength Division Multiplexing Small Form-factor Pluggable (WDM SFP)-type transceivers deeper into the network pose environmental challenges. The nodes and many outside plant cabinets that support DAA are not environmentally controlled, creating very real operational concerns when case temperatures veer outside the standard temperature envelope. New Original Equipment Manufacturer (OEM) Remote PHY nodes are requiring 10G transceivers to be rated for industrial temperatures or even more extreme over 90°C! Due to their wavelength stabilising technology, the ProLabs iTemp range of WDM transceivers can endure temperatures as low as -40°C and as high as +85°C, which enable them to perform even in the most demanding environments – enabling greater flexibility from fibre infrastructures.
Tunable DWDM transceivers have also been embraced by MSOs for efficiency for scale DAA deployments. Tunable transceivers offer maximum flexibility for operators to order and carry only one transceiver which is capable of transmitting at 80 different DWDM wavelengths. Practical challenges also apply to the deployment methods of tunables in the field as typical Remote PHY nodes or shelves do not have tuning capabilities via their respective operating systems. Peripheral tuning devices and self-tuning transceivers offer practical solutions to these challenges. Peripheral tuning devices are simple appliances that accept DWDM transceivers and enable a user to set the desired wavelength with single click prior to installation in the target environment. Self-tuning transceivers literally tune themselves to an available wavelength without additional operation by a user.
While the discussion on the expo floor was centered on overcoming the challenges of deploying DAA, the SCTE 2019 program presented a bold 10G vision for the MSO industry. The 10G vision offers a roadmap of providing 10Gbps to the customer premises using a collection of architectures based upon the new DOCSIS specification and Fibre to the Home (FTTH) technology. Does this 10G strategy mean that MSOs will be avoiding the 5G wireless business all together? Most likely not.
Today’s DAA deployments are indeed transforming the MSO network for the future. DAA is pushing fibre closer to the end user offering fibre where fibre is needed for 5G wireless fronthaul and backhaul traffic. DWDM systems offer extreme flexibility to utilise DAA infrastructure for converged network traffic. Following the discussions at the event and the 10G vision for the MSO industry, it will be interesting to see where DAA leads in 2020 and beyond.
Ray Hagen, ProLabs Americas Product Manager
