How does software-defined networking differ from virtual networking?
The architecture of a software-defined network (SDN) is designed with a separation between the control plane and the data plane (user plane). What this means is that the processing of network functions takes place somewhere other than the physical devices that are carrying the data packets to far-flung parts of the world. Centrally-managed SDN controllers dictate traffic flows and allow for agile and flexible management of the network.
The SDN architecture has three layers:
- Application layer
- Control layer
- Infrastructure layer
SDN is being strongly promoted by the Open Networking Foundation. The idea is to replace proprietary network equipment with off-the-shelf, white box switches. Linux-based servers can be configured with software to create virtual environments.
Virtual networking, on the other hand, may refer to a number of implementations. The traditional idea of a virtual network has been one that connects wide area network components using virtual links, such as VCs, VLANs or VPNs. In today’s evolving IT infrastructures, other developments lean toward different descriptions for the term. Some vendors have created virtual services switches or platforms that consolidate diverse services and functions. The aim is to simplify network infrastructure through virtualization. One of the key aspects of virtual networking is the disaggregation of software and hardware.
Overlay virtualization is a solution that is becoming more common. A form of virtual networking, topographies with no links to physical devices allow for private connections between isolated network segments. The flexibility of overlay networks makes it possible to run a variety of network traffic among virtual components in cloud computing environments. Not only virtual machines comprise this architecture, but virtualized switches, routers, firewalls, load balancers and other network appliances are possible through network functions virtualization (NFV).
Tags
Written by David Scott Brown | Contributor

David Scott Brown has more than 15 years experience as a freelance network engineer. He has worked in both fixed line and wireless environments across a wide variety of technologies in Europe and America. David is an avid reader and an experienced writer.
More Q&As from our experts
- How does artificial intelligence compare to man-computer symbiosis?
- Why are some people worried about artificial intelligence?
- What are the benefits of cloud-in-a-box deployments?
Related Terms
- Cloud Computing
- Virtualization
- Virtual Circuit
- Virtual Ethernet
- Virtual Private Network
- Software-Defined Networking
- Overlay Network
- Overlay Virtualization
- Diameter
- Network Functions Virtualization
Related Articles

AI in the Army: How Virtual Assistants Will Impact US Military Ranks

Finite State Machine: How It Has Affected Your Gaming For Over 40 Years

How Cloud Computing is Changing Cybersecurity
Tech moves fast! Stay ahead of the curve with Techopedia!
Join nearly 200,000 subscribers who receive actionable tech insights from Techopedia.
- The CIO Guide to Information Security
- Robotic Process Automation: What You Need to Know
- Data Governance Is Everyone's Business
- Key Applications for AI in the Supply Chain
- Service Mesh for Mere Mortals - Free 100+ page eBook
- Do You Need a Head of Remote?
- Web Data Collection in 2022 - Everything you need to know