Intelligent path selection drives new, cost-effective SD-WAN options
At its core, Software-defined WAN (SD-WAN) is about simplifying and automating your network — about replacing manual intervention amid changing conditions. It’s about making the network do more of the actual work that enables the Connected Enterprise’s increasingly fluid and flexible network Edge — the Elastic EdgeSM.
Until now, the benefits of SD-WAN have been confined to active-active WAN configurations. That said, recent strides in intelligent path selection capabilities combined with active-passive configurations have opened new possibilities for enterprises looking to cost-effectively leverage SD-WAN services.
This new WAN configuration — an active-dynamic WAN configuration — is a new way to think about and benefit from SD-WAN.
Active-Active WAN Configuration
In an active-active configuration, an organization simultaneously has two or more WAN sources connected and running at all times. Both sources are always on and available, and traffic can flow over whichever source is best optimized for the application. Should one link fail or become deteriorated, SD-WAN technology ensures that traffic is instantly and automatically routed over the other link without any data loss.
However, to execute this level of seamless and automated traffic steering, the solution must probe the network constantly and rapidly. This isn’t a problem when utilizing nonmetered WAN sources such as MPLS and DSL, but for metered links such as LTE, constant probing utilizes a great amount of data, making it a costly option and at times counteracting some of the anticipated savings associated with software-defined networking.
Active-Passive WAN Configuration
In an active-passive configuration, only one WAN source is active at any given time. When the primary link fails, it’s possible to fail over to a secondary source, but there’s a virtual certainty of data loss during this transition. However, active-passive requires far less data usage, making it a cost-effective configuration when using metered WAN links.
The differences between active-active and active-passive configurations are perhaps best illustrated by comparing a freeway to train tracks. In an active-active configuration, the network functions like a freeway; traffic can move on or off the freeway easily and as needed based on the conditions, destination, and contents of each “vehicle,” or packet.
An active-passive configuration is more like a railway system. When a “train,” or packet, leaves the track it’s on because of WAN failure, it is switched over to a secondary track — and the primary path is turned off. Only one track at a time can be used.
That said, with the right technology, active-passive configuration can accommodate incredibly fast WAN failover and failback — facilitating intelligent routing, yielding minimal data loss, and saving a lot of money on data usage.
Advantages of Active-Dynamic Configurations & SD-WAN
Cloud-delivered network alerts are quite helpful, but often enterprises lack the time to respond accordingly to all of the data they receive. Through Cradlepoint, policies automatically take care of many of the activities that in the past were strictly manual and eliminate data loss during the process. This solution combines the best parts of active-active and active-passive configurations – creating an active-dynamic WAN configuration.
Cradlepoint’s SD-WAN solution — including NetCloud Manager — enables rapidly deployed Day-1 networks that can route traffic based on bandwidth usage, application content, or preferred link to ensure maximum availability and uptime.
Services such as Smart WAN Selection, WAN Verify, and WAN Affinity smartly assess — with minimal data usage — the health of each WAN link and its ability to run applications. IT teams can set traffic and failover policies based on high-level business intent, then rely on routers running Cradlepoint NetCloud OS to detect an outage or a deteriorated link and automatically fail over.
Cradlepoint’s Auto-Tunnel enables optimized, resilient networks on top of multi-WAN solutions. This functionality automatically switches between WAN sources in sub-second speed, providing the best customer experience with essentially zero downtime. It also allows a secure VPN to be set up in dramatically simpler fashion. Auto-Tunnel can eliminate data loss and make active-passive configurations look like an always available connection.
To learn more about Cradlepoint’s SD-WAN solutions for today’s Elastic Edge, visit Cradlepoint’s Wireless WAN webpage.