A next-gen SD-WAN provides unified control, management and visibility with a centralized interface. Traffic is optimized for performance and adherence to business policies — whether on-premises, data centers or cloud/SaaS.
Using software intelligence, SD-WAN helps IT teams dynamically route traffic and improve user experience. It also simplifies the management of edge devices by separating network logic and configuration from physical connections and hardware.
What is SD-WAN?
Traditionally, the WAN has been one of the most difficult network areas to manage. But as enterprises expand their global presence and rely more on cloud applications, they need rock-solid connectivity to keep their employees productive and customers happy.
SD-WAN uses software to optimize WAN connections. It monitors WAN links for performance and reliability and then automatically shifts traffic across junctions based on the needs of specific apps. This reduces latency and packet loss, which improves application performance and increases employee productivity.
With some SD-WAN solutions, IT can prioritize WAN traffic and route it across cheaper public Internet links like broadband or wireless when possible. This lowers cost and eliminates the need for expensive MPLS circuits. Additionally, many SD-WAN solutions offer automatic failover and redundancy, which boosts resilience and improves application performance.
In addition, SD-WAN offers a wide range of security capabilities, including application-level firewalling that can reduce costs by obviating the need for dedicated hardware or by augmenting existing firewalls. Some solutions also use zero-trust strategies, which can further lower security costs and increase business agility.
Some solutions involve a physical appliance or white box integrating SD-WAN, routing, and security functions to provide a unified platform. Other offerings are fully software-based and run on a virtual machine or server, enabling IT to deploy them at the network’s edge, in remote sites, data centers and cloud platforms.
How Does SD-WAN Work?
Today’s high-demand applications require consistent peak performance. WAN architectures prioritizing business-critical apps deliver better user experience and lower the risk of productivity-impacting issues like latency and packet loss.
Traditionally, WANs connect branch offices to multiprotocol label switching (MPLS) networks that backhaul traffic to one or more data centers in the cloud. While MPLS networks are reliable and secure, they are expensive. SD-WAN eliminates the need for costly MPLS circuits and enables enterprises to use cheaper internet connections for application delivery while leveraging existing network infrastructure.
Instead of having separate networking and security stacks at each site, an SD-WAN device combines networking and security functions into software-native appliances that run on standard PC hardware. This reduces the cost and complexity of deployment, management and maintenance for remote sites while providing a more robust network environment for delivering business-critical applications.
An SD-WAN appliance encrypts and tunnels traffic to and from each site on the WAN, establishing a single, virtualized application-delivery path across multiple links. Traffic is routed based on policies, and the appliances learn from each other to provide more accurate and consistent routing decisions. This also allows organizations to utilize public Internet and cheaper, more flexible connections for traffic delivery rather than MPLS or other expensive circuits.
SD-WANs can work with other technologies in the network, such as firewalls and secure web gateways. These devices can share policies with the SD-WAN, eliminating the need for manual configuration. Zero-touch provisioning is also possible with some SD-WAN appliances, enabling them to phone home for initial configuration and IP address information when plugged in at new locations.
What are the Benefits of SD-WAN?
Understanding what is SD-WAN used for? A key benefit of SD-WAN is that it enables an organization to deliver WAN services more rapidly, with greater feature velocity and flexibility. This is achieved by replacing static WAN configurations with a new interface that reshapes or provides low-level packet control. This approach, commonly used in network orchestration and operations systems, is similar to software-defined networking (SDN) in modern data centers.
This contrasts traditional MPLS networks, which often need to be faster and more flexible to implement and support. They also require skilled, dedicated IT resources, driving up operational costs.
With centralized management and a simplified interface, designing, deploying, operating, and troubleshooting an SD-WAN is much faster and easier. Additionally, a well-performing SD-WAN solution will enable an organization to increase capacity as needed without the expense of upgrading infrastructure at each location.
Another key benefit is the ability to re-route application traffic over the most suitable network link based on performance and quality metrics. This allows for a better user experience by eliminating latency, jitter and packet loss. It also allows IT teams to prioritize and support business-critical applications. SD-WAN products will use probes to monitor network conditions and select the best path for application traffic. If an investigation indicates one path is failing or overloaded, it will be re-routed to a secondary link, ensuring application performance remains consistent.
What are the Best Practices for Implementing SD-WAN?
Achieving successful SD-WAN implementation requires planning, testing and establishing processes. For example, IT teams must know their business model and what they are trying to accomplish to make an informed decision about the solution that best fits them. They should also establish a budget and consider long-term costs, Danilowicz said.
Often, IT teams will employ an MSP that takes charge of the project, including procurement and relationship management with WAN providers. This option reduces time to deployment and enables IT to focus on other priorities, such as security.
Another essential SD-WAN feature is micro-segmentation, which helps IT staff isolate and prioritize network traffic. This can prevent untrusted devices from accessing the network and protect sensitive data. It can also enable IT to organize high-priority traffic to travel over the fastest link, improving performance and increasing reliability.
Finally, IT teams must be able to implement and manage policies across the entire network in an easy way. This can be done using a single UI that provides templates, eliminating device-by-device configuration and the need for manual, error-prone processes.
A successful implementation of SD-WAN can provide many benefits, including lower operational costs, higher employee satisfaction, and greater productivity. By allowing businesses to utilize different connectivity options, such as MPLS and broadband internet, while also providing a central management system, SD-WAN technology offers the flexibility to meet business needs.