NFV and SDN – A Comcast Perspective


Embracing open source has seen Comcast transform from a cable company to a networking company and now to a software company, highlighted Nagesh Nandiraju, Director of Next Gen Network Architecture, Comcast in his plenary talk at Open Networking Summit 2016.

“Underlying all of this requires a big cultural shift, which is not easy when the network is software driven.” Nandiraju said about the transformation as a software company. “We are undergoing some of these transformations in our company in terms of realizing the power of software from the networking perspective.”
Nandiraju presented Comcast’s vision on application of SDN and NFV, important use cases and concerns as a service provider consumer of open source networking technologies.

He started with an overview of key transitions experienced by service providers:

  • Customer trends: The three key customer trends are single gateway devices in customers’ homes becoming network within homes as a result of increasing devices; evolution of service mobility from cellular mobility to service availability on any device on the go and imminent proliferation of devices with Internet of Things.
  • Service Provider  trends: As a service provider definition of service is continuously evolving and it is important to adapt and provide services that cater to customer trends as well as enable growth applications. The challenge is in decoupling these services from the underlying network without a minimal impact on the network.
  • Access Technologies and Architecture: Comcast has a substantial amount of access network primarily driven by DOCSIS technology equivalent to broadband network gateway similar to the telco world. There are different parallel technologies doing the same thing, but they exist as vertically integrated boxes and the goal is to leverage synergies across these technologies.

Then Nandiraju shared how Comcast’s vision for application of SDN:

  • Overlay Networks: Comcast’s approach is to apply SDN on an overlay network building L2/L3 VPNs for end customers and leverage service chaining to enable services and introduce network elements in a dynamic way and grow them elastically.
  • Network Automation: The goal is getting to an end state where the network is programmable and smart while requiring minimal human touch.
  • Merchant Silicon: Simplify core and edge network by leveraging merchant silicon with focus on segment routing while transitioning away from MPLS.
  • Telemetry & Analytics: Applying big data and machine learning principles to software-defined networks and enable a smart network.

“We are investigating and exploring all the different functions that can be virtualized and what makes more sense, because there is a reason why they were purpose built. And how and when and what applications have to be migrated.” said Nandiraju as he briefly discussed two key use cases Software Defined L3 VPN service as well as Uniform Services over Multiple Access Networks.

Finally Nandiraju outlined the common concerns in NFV / SDN adoption as a service provider including too many options, diverse skill set needed for integration, virtualization and its impact on service chain, new operational processes and tools and business challenge of balancing new products and services with operational efficiencies.
Watch the full talk, ‘NFV & SDN – A Comcast Perspective’ below.