As described, vCPE and SD-WAN technology cover a lot of potential network scenarios and use cases. It’s important to understand how the vCPE, SD-WAN and VNFs fit together and where will the technologies be installed.
Overall, the best way to describe what is happening is the move from discrete, specialized services networks, in which each service is built out with separate hardware and software components, to a more modular architecture in which a general hardware and software platform – using NFV – can be installed in a data center to support the rollout of services, including vCPE and SD-WAN.
Virtual Edge Taxonomy
This modular approach requires a flexible collection of vCPE, SD-WAN, and VNF technology functionality that can fill out different pieces of the next-generation WAN architecture. Here are some definitions of the pieces of the puzzle:
vCPE: vCPE technology is used to allow proprietary hardware and software to be replaced with virtualized instantiations that may run at customer premises (sometimes on lower cost equipment), in central offices (CO) or points of presence (POPs), or in data centers. Many vCPE architectures provide hybrid approaches that allow different functions to run in different locations to optimize for latency, manageability and cost.
SD-WAN: The SD-WAN extends beyond the virtual CPE, into the core of the WAN or service-provider network. It enables service providers and enterprises to leverage existing physical CPE or vCPE technology to create fully managed multi-site networks, which may integrate links using the Internet and private networks, such as MPLS. Typically, SD-WAN architectures reflect disaggregation of the control and data plane and improved flexibility and programmability common across SDN solutions..
VNFs: Virtual Network Functions as used in this report primarily refer to the valued-added L4-7 services that can be layered on top of the SD-WAN once it is built.
The diagram below represents a full SD-WAN network, including different POPs where vCPE devices and SD-WAN controllers might be placed.