qstockmedia - Fotolia

How does software-defined access work?

Service providers and enterprises use software-defined access to extend SDN beyond the data center and WAN to the edge of the network. Learn about its developments and benefits.

Software-defined access can refer to one of two things, depending on its service provider or enterprise context.

For network service providers like telcos or cable companies, software-defined access refers to bringing SDN tools and benefits to the customer-facing edge of the network and to the customer premises equipment that delivers services. Overlap can exist between a service provider's software-defined access offering and its software-defined WAN service.

With software-defined access, services are delivered by software components that run on commodity hardware platforms, rather than telco-specific, service-specific appliances. This may involve virtualized appliances or smaller-scoped virtual network functions orchestrated and chained together to form a broader network functions virtualization framework.

Software-defined access typically will have full APIs available, so they are fully programmable and can be operated with automation tools.

Benefits for service providers

Software-defined access typically will have full APIs available, so they are fully programmable and can be operated with automation tools.

For the service provider, the benefits of software-defined access mirror the benefits of SDN more broadly:

  • Agility. Software-defined access puts network services' development and deployment on a software time frame, rather than on a custom hardware time frame.
  • Independence. It replaces specialized, proprietary hardware at the edge with generic x86 and commodity switching functionality.
  • Efficiency. Software-defined access is automation-friendly and reduces the number of staff hours required to deploy new services or to modify the delivery of existing ones -- e.g., driving bandwidth increases on a dynamic link.

In combination, these factors mean service providers can try new things more quickly, with less capital overhead and lower investment of staff time and effort. They can better respond to client requests and needs, modify an offering to serve new clients more quickly and refocus development on promising opportunities -- all without rolling trucks and replacing racks full of specialized hardware.

Software-defined access in enterprise context

For enterprises, software-defined access can mean using SDN outside the data center and WAN, extending it all the way to the user access edge of campus switching and wireless LANs. Although this capability has been around in theory since the birth of SDN -- and in practice at a small number of SDN adopters for many years -- it has only come in to wider discussion in the last year or so, as Cisco rolled out its intent-based networking strategy.

In addition to some of the same benefits that service providers achieve, enterprises get more consolidated, consistent and simplified management through a central controller. Software-defined access also offers enterprises the ability to apply security and access policies consistently across all parts of a network.

This was last published in November 2018

Dig Deeper on Network Infrastructure