In the final of a two part article, Jon Baldry the metro marketing director at Infinera, says DAA offers exciting opportunities, but migration to this new architecture presents a raft of new challenges. Fibre and dense wave division multiplexing (DWDM) pushing deeper into the access network from the secondary hub to remote RPDs means a tenfold or so increase in the number of end points for the DWDM network. Secondary hubs will now also have to aggregate 100s of 10Gb/s circuits from RPDs into efficiently filled 100Gb/s backhaul circuits to the primary hubs. These secondary hub locations are often already space and power constrained and when they aren’t, operators may look to consolidate secondary hubs, creating a space and power constrained environment.

Selecting suitable equipment will no longer be a simple matter of asking a preferred supplier to meet the required performance levels, it will be necessary to look closely at the specifications to see if devices are sufficiently compact and power efficient to optimise scarce secondary hub real estate and to provide additional capabilities that can address the significant operational challenges of managing such a high density aggregation. With a tenfold or so increase in the number of RPDs terminating the DWDM network, installation and operating expenses will soar unless care is taken to choose the most compact, reliable and easy to maintain equipment.

Optical equipment suppliers are aware of these concerns and are rising to the challenge of mass deployment of DAA networks. Great advancements are being made in terms for density, power consumption and addressing the operational challenges of managing potentially thousands of fibres within a secondary hub rack. What’s more, the industry has been working to bring the International Telecommunications Union’s (ITU) vision of autotuneable WDM-PON optics up to the performance levels required to support the reach and capacity requirements of DAA networks. This eases the pressures of commissioning and maintaining extensive DWDM optical networks by replacing the technicians’ burden of determining and adjusting wavelengths at every installation. Autotuneable technology will automatically select the correct wavelength without any configuration by the remote field engineer enabling them to treat DWDM installations with the same simplicity as grey optics.

These are the sort of challenges that will be faced as MSOs migrate to DAA, and they will need to take a very close look at their choice of equipment and solutions in order to meet the very specific challenges of fibre-deep access networks. However, a successful DAA rollout is not just about what happens in the access network. DAA will also create a surge in bandwidth demand throughout the entire infrastructure – from access through transport to core. Unless steps are taken to reinforce, optimise and automate the entire network capability, the most powerful, responsive and efficient access network could become its own worst enemy.

Already nearly a half of all US consumers are using streaming video services and 70% binge watch TV series, while virtual and enhanced reality services and 4K high definition TV are still poised to go mainstream. So future-proofing a cable MSO’s network means preparing for a highly uncertain future.

CSPs will need help from specialist optical equipment providers to optimise optical transport platforms to their specific needs, creating network architectures that will be highly scalable, that simplify operations, accelerate the launch of new services, and minimise total cost of ownership. Something that will only be achieved by installing intelligent networks that integrate best-in-class technology and automate a significant proportion of manual operations.