Traditional WANs based on conventional routers are not cloud-friendly. They typically require backhauling all traffic – including that destined to the cloud – from branch offices to a hub or headquarters data center where advanced security inspection services can be applied. The delay caused by backhaul impairs application performance resulting in a poor user experience and lost productivity.
Unlike the traditional router-centric WAN architecture, the SD-WAN model is designed to fully support applications hosted in on-premise data centers, public or private clouds and SaaS solutions such as Salesfore.com, Workday, Office365 and Dropbox, while delivering the highest levels of application performance.
SD-WAN delivers increased network agility and cost reduction. Software-Defined WAN has its roots in Software-Defined Networking (SDN), the underlying principle of which is to abstract the network hardware and transport characteristics from the applications that use the network.
To stay competitive in today’s age, organizations are constantly evolving to overcome branch challenges such as expensive bandwidth, the complexity of the branch network and rigid architecture. Numerous single-function devices in the branch leading to device sprawl with silo management needing multiple truck rolls to deploy, monitor and troubleshoot. Branch WAN traffic hair-pinning through datacenter degrades cloud application performance. Provisioning new applications for branch use requires re-configuration and is IT intensive.
SD-WAN counters these with 2 key features:
- Centralized Orchestration. By centralizing the configuration of an SD-WAN as well as application performance and security policies, enterprises can significantly reduce WAN operational expenses.
- Zero-Touch Provisioning (ZTP). With ZTP, configurations and policies are programmed once and pushed to all branch locations without having to manually program each device individually using a CLI. It eliminates the need to send specialized IT resources out to branch locations whenever a new application is added or a policy is changed. ZTP also reduces human errors, resulting in more consistent policies across to enterprise.
The traditional router-centric model that backhauls traffic from the branch to headquarters to the internet and back again no longer makes sense.
Backhaul adds latency – or delay – that impairs application performance resulting in poor user experience and lost productivity. Employees often report that their business apps run faster at home or on their mobile devices than at the office.
Geographically distributed enterprises are embracing SD-WANs at an accelerating pace because they help businesses become more agile, enhance business productivity and dramatically lower costs.
VMware’s Velocloud, the market leader of SD-WAN technology, stated that SD-WAN benefits organizations in 5 ways:
• Increased business productivity and user satisfaction
• Enhanced business agility and responsiveness
• Improved security and reduce threats
• Simplified branch WAN architecture
• Reduced WAN costs by up to 90 percent
This seems to be the case as SD-WAN solutions provide the software abstraction to create a network overlay and decouple network software services from the underlying hardware. As applications continue to migrate to the cloud, networking professionals are quickly realizing that traditional WANs were never architected for the cloud.