What's at the End of the CORD?
The whole notion of a Central Office Re-architected as a Data Center (CORD) is the telecom industry's way of taking innovative data center technologies, including virtualization and software-driven services, and feeding them into the broadband access network.
But does CORD work? And if so, what value is it delivering?
During a session on "The Next-Gen Central Office/Headend" at Light Reading's recent Big Communications Event (BCE), panelists had some early conclusions to share. Among them, and perhaps most notably, the CORD approach appears to generate returns faster by creating new revenue streams than it does by helping operators save money through network upgrades.
CenturyLink Inc. (NYSE: CTL) Director of Network Architecture Bill Walker explained how his company has used CORD as a reference architecture for its DSL infrastructure, including virtualizing broadband network gateway (BNG) equipment and running over-the-top services on commercial off-the-shelf (COTS) hardware. The theory was that CenturyLink would save money by moving away from expensive, dedicated hardware in its central office locations. (See CenturyLink Delivers DSL Using CORD Platform.)
As it turns out, however, the company's had an easier time realizing gains through new service introductions enabled by the CORD implementation than it has through equipment cost savings.
"In reality it's profitable. We've generated revenue. But we're actually struggling more with the pieces that were going to save us money," said Walker. He added that new services, like network-based security and SD-WAN, are what's driving the financial success of CenturyLink's CORD deployment today.
According to Walker, bandwidth also continues to be one of the major drivers for implementing CORD. Specifically, by disaggregating hardware and making systems more modular, it's possible to better prepare for whatever challenges the next wave of bandwidth demand brings. Walker said CenturyLink and others weren't ready for the Netflix phenomenon, but they will be for future applications.
Robert Conger, VP of Cloud and Portfolio Strategy at ADTRAN Inc. (Nasdaq: ADTN), agreed, pointing out that when operators are using highly integrated hardware and there are spikes of demand, it's difficult to make targeted network upgrades. But with a modular system, it's easier to drop in capacity where it's needed.
"They need that modularity. They need that system with interchangeable parts because they don't know what's coming next," said Conger on the BCE panel.
Unfortunately with a CORD architecture, there's no one-size-fits-all approach, particularly across different types of access networks with different types of legacy equipment. There are some common themes popping up among service providers, however.
Conger noted, for example, that where optical line terminals (OLTs) for FTTH deployments are concerned, all of Adtran's customers are looking for solutions that at least include a path toward software-based control, even if operators aren't ready to fully virtualize OLT functions today. Customers are also demanding technology that's open and not locked into a single vendor ecosystem.
There are similar conversations taking place in the cable industry around HFC architectures. Cable operators are looking to their vendors for a migration strategy that will lead them from proprietary headend hardware -- cable modem terminations systems (CMTS) or Converged Cable Access Platform (CCAP) chassis -- to software-defined solutions that can run on COTS servers. (This is sometimes called Headend Re-architected as a Data Center or HERD.) As an intermediary step, many cable companies are considering distributed access architectures that move some functions of cable hardware deeper into the network and introduce new software for automating equipment configuration. In the long run, however, the expectation is that fully virtualized CMTS/CCAP chassis will be available. (See The Cable DAA Vendor Race Begins and Cable's DAA Moment Is Here.)
Conger believes that the move toward 10G PON will help drive the CORD trend. As operators plan capacity upgrades in their fiber networks, they'll also explore more modern approaches to managing that infrastructure.
"[I] think it's going to be extremely disruptive over the next ten years," said Conger, referring to the combination of 10G PON upgrades and CORD strategies.
The trend has already started. Conger declared on the event panel that at least ten tier-one operator customers are involved in 10G PON deployments where new software-driven systems are part of the upgrade. It's still early days in 2017, but 2018 could be the year that 10G deployments aligned with CORD implementations really take off.
— Mari Silbey, Senior Editor, Cable/Video, Light Reading