Technology changes often create a domino effect, requiring cascading adjustments throughout the IT
environment. That is certainly true of the ongoing shift to cloud-based applications and services.
The cloud is instrumental in supporting new work-from-anywhere models, providing organizations with access to many of the essential applications they need to remain operational. In fact, cloud app adoption nearly doubled last year to an average of 2,415 apps per organization, according to Netskope Research Labs.
Although cloud apps deliver undeniable business benefits, they also create significant challenges for conventional wide-area networks (WANs). In response, organizations are accelerating their adoption of software-defined WAN (SD-WAN) technology to accommodate this fundamental change in application delivery.
Traditional WANs allow workers in branch or remote offices to access applications from the company data center across dedicated MPLS connections. However, all Internet traffic — including traffic to and from the cloud — must be backhauled to the data center where advanced security services can be applied. That’s fine for email or web browsing, but backhauling cloud application traffic creates extreme latency issues that result in inconsistent application performance.
SD-WAN’s virtualized infrastructure fully supports applications hosted either on-premises or in the cloud. Remote users can securely access cloud services directly without backhauling. Cloud connectivity is further optimized through application-aware routing, traffic prioritizing, automated provisioning and other sophisticated features.
Most important, SD-WAN doesn’t depend entirely on “best effort” Internet connections that won’t always provide the reliability necessary for application traffic. According to research by VMware, Internet links fail to deliver the performance required by real-time applications 17 percent of the time — unacceptable for mission-critical cloud services.
SD-WAN ensures quality connectivity through the use of multiple transport types such as MPLS, broadband Internet, cellular and satellite to ensure connectivity. Software-based intelligence dynamically tracks application and network characteristics to route traffic over the optimal connection. In addition, SD-WAN allows administrators to assign policies to prioritize traffic based on business requirements. For example, business-critical voice and video apps requiring near-real-time data transfers are typically given the highest priority transmission status.
Multipath technologies also improve connectivity by allowing dual links to be used simultaneously. For example, VMware’s SD-WAN solution uses Dynamic Multipath Optimization (DMPO) to aggregate bandwidth over two links to improve throughput. VMware says this approach delivers enterprise-quality application performance 99.3 percent of the time.
DMPO also provides continuous link monitoring to optimize connectivity. If it detects congestion, it automatically moves traffic to the best link. If both links experience congestion, the system sends duplicate packets in real time over both links to ensure that they get through.
None of this is practical with a conventional WAN. Differentiating workloads, segmenting traffic and choosing transport mechanisms is theoretically possible, but it would require a series of manual changes to network configurations and routing protocols at every remote location — all of which would have to be updated regularly as application profiles and operational requirements change.
The cloud enables new operational options by supporting the application requirements of highly decentralized workforces. However, the increasing dependence on cloud-based applications also creates network demands beyond the scope of traditional WAN architectures. SD-WAN solutions help ensure remote, mobile and branch-office employees have reliable access to the applications and data they need.