Due to cost factors, companies are now more inclined to implement MPLS-like performance using inexpensive broadband links. One option is to use overlay tunnels on heterogeneous WANs and add the ability to control traffic steering on these links. Traffic steering rules can be used to control the behavior of different types of traffic on each site. This way, companies can use any available WAN link based on business needs.
The SD-WAN is part of the WAN Edge Technology Suite, which can process packets at wire speed according to the template rules provided by the central SD-WAN controller. Therefore, SD-WAN has similarities to the SDN concept. As in SDN, the control plane (defined traffic steering rules) is moved to the centralized controller and the data plane (executing traffic steering rules) stays on the customer edge device. Therefore, a centralized SD-WAN controller is used to control SD-WAN devices installed in customer premises or sites. Since SD-WAN does not require routers to be configured in the WAN (this is required in MPLS for resource reservation on each label) and the development of a fast packet processing engine based on content addressable memory, SD-WAN Both equipment and operating costs are an order of magnitude cheaper than MPLS.
How does SD-WAN help?
More and more companies are deploying SD-WAN solutions to address the challenges of MPLS. The SD-WAN is opaque on the transmission path, so SD-WAN overlay tunnels can be created on any WAN link (MPLS, Internet, LTE, 4G) at the enterprise site.
To save bandwidth consumption of the MPLS link, the SD-WAN moves less critical applications over the SD-WAN tunnel of the alternate WAN link (Internet). Enterprises can define flow control rules for each application. With a centralized SD-WAN controller, these flow control rules are looped through to the SD-WAN device. All types of data traffic pass through this SD-WAN device and are processed according to the configured rules. For example, an SD-WAN controller might configure a site to use MPLS for VoIP connections, while an O365 application uses an Internet connection.
To support faster access to applications running in the cloud, SD-WAN can configure traffic steering rules to use Internet connectivity for these applications. As a result, cloud traffic is transmitted directly from the branch to the Internet rather than backhaul to the headquarters. Some SD-WAN operators can directly access cloud data centers (such as AWS or Microsoft Azure) from their gateways to improve the performance and reliability of applications hosted on these clouds.
In addition, SD-WAN provides WAN optimization features such as data replication, data compression and forward error correction. These optimizations reduce WAN bandwidth requirements and provide better QoS. These WAN optimizations are value-added services in most SD-WAN solutions.
Easily manage with SD-WAN
The SD-WAN solution provides centralized monitoring and analysis support. On each SD-WAN tunnel and site, measure the performance of the application against the required metrics. These metrics are reported to the SD-WAN controller. Based on the configured traffic steering rules and reporting metrics, the controller can identify anomalies in the network. Therefore, users can modify business-oriented rules to improve application performance. Analysis support can be used to predict potential policy changes or recommend changes to users based on real-time data.
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