A Software-defined Wide Area Network (SD-WAN) is a virtual WAN architecture that provides enterprises with the flexibility to leverage any combination of transport services, including broadband internet, to securely connect users to applications. Today, applications are hosted in on-premise data centers, and increasingly in private or public clouds. Or they may be consumed as a subscription-based Software-as-a-service (SaaS) offering. Typical SaaS examples include Salesforce.com, Workday, Office365, Box and Dropbox.
An SD-WAN virtualizes WAN services including Multiprotocol Label Switching (MPLS), broadband and 4G/LTE, treating them as a resource pool. Pre-defined policies, programmed by IT, specify per application group how traffic should be handled to meet priority, Quality of Service and security requirements according to business intent. An SD-WAN continuously monitors applications and network resources to intelligently and automatically steer traffic in accordance with these requirements in contrast to conventional routing based on TCP/IP addresses.
- All SD-WANs Are Not Created Equal
- While an SD-WAN is a critical component of building a better WAN, a complete solution must address a broader set of requirements:
- Performance – Deliver predictable application performance and quality of service across the WAN
- Visibility and control – See and control all applications and data running across the WAN
- Security – Secure and segment all WAN traffic and applications
- Extensibility – Able to service chain other WAN services and route across the WAN
SD-WAN is normally used as in organization where it allows to connect the links together with different location through the use of broadband and MPLS. It mainly focus on delivering data to wide area networks which connects multiple sites together. If you compare the same concept with SDN it actually used to create networks that can be modified quickly in line or adapting change in the enterprise systems. SD-WAN is mainly design to sustain WANs network over a large geographical area to provide flexibility, reliability and sustainable network with multiple paths. An SD-WAN service is managed by a vendor. That means SD-WAN is simple enough to deploy in terms of administrator because the user isn’t responsible for providing any service and access to different enterprise networks.
SD-WAN also has the advantage of supporting services like VPN as well. Many organizations are using SD-WAN as a way to underpin their VPN. SD-WAN is rising very fast because this service makes network management more simple agile and less costly as all services are provided by the administrator.
IDC estimated in July 2017 that worldwide SD-WAN infrastructure and services revenues would grow at a compound annual growth rate of 69.6 percent and reach $8.05 billion in 2021. Meanwhile, Gartner has predicted that by 2020, more than 50 percent of WAN edge infrastructure refresh initiatives will be based on SD-WAN compared to traditional routers.
How Does SD-WAN Work?
For example, voice calls and credit card transactions can go over MPLS switching while YouTube uses a broadband connection. SD-WAN lets companies set policies so that the network can do that automatically, Altas said, “so that the IT people don’t even have to know it. They can set it and forget it.”
Wide area network helps companies to support their business critical situation including network related problems servers, virtual Desktops, video conferencing platform apps and enterprise resources planning. So all these things require a lots of network bandwidth and also need good QoS(quality of service) with reliable connection.
SD-WAN allows businesses to create hybrid WAN architectures that use multiple kinds of connections different paths, essentially — to automatically create the best network path for the apps running on the network. It enables certain apps to be prioritized over other, less important network traffic. This can be done at a granular level and managed via a centralized software controller.
Types of SD-WAN Architecture
SD-WAN provides three types namely, premises-based, MPLS-based, and Internet-based.
- Premises-based SD-WAN solutions involve an appliance that is placed onsite to achieve SD-WAN functionality. Premises-based SD-WANs can be cost-effective solutions for smaller, localized businesses.
- MPLS-based SD-WAN solutions involve multiple appliances placed at network endpoints. These solutions create a virtual IP network between the vendor-proprietary appliances, giving them control of network packets from end to end.
- Internet-based SD-WAN solutions also use multiple appliances at each customer location, using public Internet connections from customer-chosen providers. The customer pays for a portion of its Internet connections to be SD-WAN.
If any enterprise company has many locations through out the world than SD-WAN is the good solution it will give realiability and cost saving. It can also handle unlimited bandwidth as per customer requirement.