Cable MSOs (multiple system operators) remain the dominant supplier of broadband services across the country, with research suggesting that cable companies will carry around 62 percent of the U.S. residential broadband subscriber market by 2026.
But heavy is cable’s crown. With that dominance comes an expectation to keep setting the pace, particularly as fiber access deployments by the telecommunications behemoths become prevalent. For that reason, MSOs across the board are having to modernize their network infrastructure to enhance customer experience, achieve operational efficiencies, and deliver new services.
Recent updates to HFC (hybrid fiber/coax) and DOCSIS (Data Over Cable Service Interface Specification) networks offer a robust transitory path to fully compete in an eventual fiber-ubiquitous world. The rollout of remote PHY devices over Ethernet/IP networks provide fertile ground for the necessary overlay of customer fiber endpoints over time—until it’s all fiber, of course. Still, the transition can’t be sustained if it increases the complexity of the operating environment and makes the network difficult to manage and support—and more costly to operate.
The question is, then, how can the fiber transition be made less complex, especially in the presence of other moving parts?
Enabling broadband with next-generation PON
PONs (passive optical networks) are not new. PON is a technology that uses fiber-optic cables to deliver services to multiple users via a point-to-multipoint access network. The key here is the fiber medium itself, which is capable of virtually unlimited bandwidth for huge transfers of information that can support both current and future services. And it’s a reason why PON is the technology of choice in discussions of Web 3.0 and metaverse transitions.
Around the world, PON has become increasingly popular as a last-mile option, especially with legacy EPON (Ethernet PON) and GPON (gigabit PON) running out of steam. The competing targets in broadband now are toward 10G, with spending on new PON equipment expected to continue for the foreseeable future.
PON technology has evolved to the point where it can enable the next steps beyond 10G, offering MSOs the opportunity to leverage their new Ethernet access to deploy long-lasting platforms that can span several PON technology cycles. There is also now granular PON technology that allows for the surgical introduction of PON via micro-optical line terminals (uOLTs), offering an ideal solution for operators who are evolving their HFC plants.
Traditionally, PON applications have been supported by large, bespoke OLT chassis deployments. But this has not been ideal for MSOs because these deployments require costly new buildouts of trunking fibers. Fortunately, the evolution of technology and design has led to the development of ‘pluggable’ uOLTs that combine an OLT laser with an embedded Ethernet MAC (media access control). The pluggables fit in a 10G SFP+ optical transceiver routing and switching port, and the methodology also allows for evolution to 25G and 100G PON solutions as those technologies become available.
vBNG: Software-defined for greater agility
Yet another transition taking hold in the broader service provider space—and with several MSOs—is the use of native cloud computing for the virtualization of subscriber management tasks. In the case of DOCSIS networks, it’s vCMTS (virtual cable modem termination system) applications. With PON, however, there are choices. One option is a software shim layer with interfaces into a DOCSIS OSS (operations support system), effectively applying the functions of long-established DPoE (DOCSIS provisioning over EPON) or DPoG (DOCSIS provisioning over GPON) specifications. Another choice is a cloud-based vBNG (virtual broadband network gateway), which makes it possible for subscriber management policy to be enabled directly without the use of DOCSIS; this is being explored by several operators.
The ability to deliver network functions virtually in the cloud provides MSOs with the agility, reliability, and scalability required to deliver high-value broadband services to residential and enterprise customers. Operators adopting vBNG can also experience the benefits of scale without the need for extra hardware, including integrated functions such as DHCP (Dynamic Host Configuration Protocol) and CGNAT (carrier-grade network address translation). Additionally, vBNGs built on CUPS (control and user plane separation) principals can provide ultimate deployment flexibility. Similar to what uOLTs did for PON solutions in hardware, vBNGs can ensure scalability at speed and added agility to adapt to changing environments in software.
MSOs keep the broadband crown by doing more with less
Ultimately, the MSOs that do more with less are those that will find varied ways to achieve their vision for 10G and beyond with networks that are agile and ready for the leap to upcoming technologies. If executed correctly, it will be tough for contenders to the residential broadband throne to wrestle away cable’s crown.
Fernando Villarruel is Chief Architect, MSO Practice, at Ciena.