In the last several years, the role of compute resources has increased the demands upon modern cable regional and access networks. Computation has quickly become part of network infrastructure itself, beyond just supporting services, over-the-top applications, and management tasks. At the same time, advancements in silicon and optical technology allow for a re-examination of cable network topology and service placement. This blog examines some key decision points the cable industry needs to consider as we work together to build the next generation of a Modern Cable Network.
The Growing Role of Compute
Computing has always played an important role in Internet systems. Network services such as DNS and SMTP, as well as applications such as web services, video cache, and the control planes of routers themselves, all depend on general-purpose compute systems being distributed in the network. Some of these compute resources are discrete servers, some are in large cloud computing environments, and still others are co-resident in routing devices. But they all share the same fundamental trait – they keep and maintain application and/or network state, they run generally available operating systems, and today, all use common x86-based CPU’s.
As computational power has grown, the ability for compute resource to perform stateful transformation of data has highly useful applications. In other words, the ability for a resource to take input from an app or the network, transform that input in some way, and return it in a more useful state. Examples of this could be real-time face recognition, such as identifying individuals in video streams. Raw video is fed into a resource, software analyzes the raw video, and returns a structured set of data. Or real-time speech to text, such as that present on modern smartphones. Raw audio is fed into an application, software deciphers the language present, and returns ordered text to be fed into additional applications.
The key is that as computation is used for more real-time, stateful transformation of data, the ability to access those resources quickly and reliably becomes paramount. And this directly translates into the latency, or the amount of time on a wire, between the end-user and that, compute resource. Ultimately, we’re talking about the speed of light.
Low latent access to real-time computation is among the most lucrative, and untapped, resources present on cable networks. Network technology is advancing to make the placement of computation in cable networks much more advantageous to this new opportunity.
Advent of New Network Technology
While demand for low latent computing starts to grow, the cable industry faces some decision points to make. New network technology is permitting a massive disaggregation, and re-architecture, of cable access and metro networks.
Distributed Access Architecture (DAA) systems, such as Remote PHY, enable the pervasive use of IP and Ethernet transport in the access layer, where the previous legacy HFC analog transmission was used.
Virtualized CCAP, such as Cisco’s Cloud Native Broadband Router (cnBR), leverages Remote PHY technology to build a scale-out, software-oriented, microservices-based analogy to a contemporary CMTS. A key point of the cloud native software architecture of the cnBR is the use of the network to place all, or parts, of the system’s functionality to anywhere the network topology extends.
Next-generation silicon, optics, software. New routing platforms, such as the Cisco 8000 series, leverage next-generation forwarding ASIC technology to deliver unprecedented capacity and systems simplicity, all in a power and space-efficient package. Coupled with emerging Digital Coherent Optic (DCO) technology such as 400G-ZR and ZR+ pluggables, it is possible to build a cable metro topology that is much more interconnected, with traffic patterns that follow the value of a dollar and not strictly the path of a wavelength. What this means is, compute can be placed in arbitrary locations, to where packet latency to it is optimal for the application.
A key compute resource that needs consideration for placement is the cnNR or Virtualized CCAP itself. A centralized vCCAP gains efficiency in software economies of scale. But a distributed vCCAP permits the opportunity to offload routable traffic closer to subscribers, which means closer to an edge compute or low latent access to compute architecture. Careful thought needs to be applied when designing the cnBR or vCCAP as a portion of overall network design and goals.
DOCSIS 4.0 also plays a role in a Modern Cable Network. To learn the latest with this standard, attend our webinar: DOCSIS 4.0 Evolution in the Cable Plant, Are You Ready. If you would like to chat more about architecting and designing the next generation of a Modern Cable Network, stop by our virtual exhibit at SCTE-IBSE Cable Tec Virtual Expo.