For enterprise network leaders, the traditional approach to networking—based on proprietary hardware and manual configuration—is becoming increasingly complex and difficult to manage. Software-Defined Networking (SDN) is a new approach to networking that decouples the network control plane from the data plane, allowing you to manage your network through software. This article provides an introduction to SDN and explores how it is impacting the enterprise by creating a more agile, secure, and manageable network infrastructure.
At its core, SDN is about centralizing control of your network. In a traditional network, the control plane (which makes decisions about where to send traffic) and the data plane (which forwards traffic) are tightly integrated in each network device. In an SDN network, the control plane is centralized in a software-based controller, which gives you a programmable and holistic view of your entire network. This allows you to automate network provisioning, to optimize traffic flow, and to enforce security policies in a more consistent and efficient manner. For a deeper dive into modern infrastructure, see our article on the top IT infrastructure trends.
The Key Components of an SDN Architecture
An SDN architecture is composed of three key components:
- The Application Layer: This layer includes the applications and services that consume network resources, such as business applications, firewalls, and load balancers.
- The Control Layer: This layer includes the SDN controller, which is the brain of the network. The controller has a centralized view of the entire network and is responsible for making decisions about where to send traffic.
- The Infrastructure Layer: This layer includes the physical network devices, such as switches and routers, that forward traffic based on the instructions from the controller.
The Benefits of SDN
The key benefits of SDN include:
- Increased Agility: SDN allows you to provision network resources and to deploy new services much more quickly than with a traditional network.
- Improved Security: SDN provides a centralized point of control for enforcing security policies across your entire network.
- Reduced Costs: SDN can help you to reduce your costs by automating network management tasks and by allowing you to use commodity hardware.
- Increased Innovation: SDN provides a programmable network that can be used to create new and innovative applications and services.
| Benefit | Traditional Networking | SDN |
|---|---|---|
| Agility | Manual provisioning and slow to change. | Automated provisioning and rapid change. |
| Security | Decentralized and difficult to manage. | Centralized and easy to manage. |
| Cost | High, due to proprietary hardware and manual management. | Low, due to commodity hardware and automation. |
| Innovation | Limited, due to the closed and proprietary nature of the network. | High, due to the open and programmable nature of the network. |
SDN and the Future of Networking
SDN is a key enabler of a number of other important networking trends, including:
- Network Functions Virtualization (NFV): NFV is the practice of virtualizing network functions, such as firewalls and load balancers, and running them on commodity hardware. SDN and NFV are often used together to create a more agile and cost-effective network infrastructure.
- Intent-Based Networking (IBN): IBN is a new approach to networking that allows you to define your desired business outcome, and then the network automatically configures itself to achieve that outcome. SDN is a key enabler of IBN.
- Secure Access Service Edge (SASE): SASE is a new security model that combines networking and security into a single, cloud-native service. SDN is a key component of a SASE architecture.
Conclusion
Software-Defined Networking is transforming the way that enterprises build and manage their networks. By decoupling the control plane from the data plane, SDN provides a more agile, secure, and manageable network infrastructure that can support the demands of the modern enterprise. As you develop your networking strategy, be sure to consider how SDN can help you to build a more intelligent and competitive business. The journey to SDN is a marathon, not a sprint, but with the right strategy and the right partner, you can unlock the full potential of this new wave of technology to create a more agile and innovative enterprise. For a deeper dive into network security, see our guide on network segmentation best practices.
