What is SD-WAN?

SD-WAN stands for Software Defined Wide Area Networking. It’s a combination of Software Defined Networking (SDN), which was created for use in cloud datacenters, and Wide Area Networking (WAN) which is the network outside of your office (e.g. the Internet, or site-to-site networks like MPLS) It simplifies enterprise connectivity to remote locations and branch offices, providing needed flexibility, centralized control and monitoring, and reducing WAN costs.

Most applications and services are being consumed in the cloud, such as Salesforce, Azure/AWS, Hosted Voice, Contact Centers, Office 365, etc. It is much more efficient to route traffic from each location directly to the Internet to consume these services rather than have a  MPLS network where you have to go back to a central site, then hit the Internet.

Top Line Benefits of SD WAN

  • Cost: Internet links are generally much less expensive than carrier-grade MPLS connections, which are typically encumbered by long provisioning times and expensive contracts.
  • Agility: Provisioning can be much quicker, can be installed anywhere you can obtain internet circuits, typically no build-out timelines or costs and the underlying telecommunications carriers can be vendor neutral.
  • Security: An SD-WAN can improve network security by encrypting WAN traffic as it moves from one location to another, and by segmenting the network so that if a breach occurs, the damage is minimized. CTG has the experience to look at the overall security impacts and what environments SD WAN can be used in where tight security and complacency needs are present.
  • Reliability: MPLS networks typically offer highly reliable packet delivery. Internet up-links, on the other hand, often fail. To compensate for this fact, many organizations that move entirely to SD-WANs choose to order multiple internet links from different providers to maintain availability in the case of link failure. In times of a circuit failure, fail over can occur almost immediately, all but eliminating downtime.
  • Performance: SD-WAN technology uses the internet to create secure, high-performance connections, eliminating the backhaul penalties imposed by MPLS networks. This allows SD-WANs to deliver business applications cost-effectively while optimizing Software as a Service (SaaS) and other cloud-based services
  • Aggregated bandwidth: This is not purely fail over or load balancing. This functions at the packet level or are implemented session by session it is a true aggregation of bandwidth. SD-WAN routers can combine the bandwidth of all types of  WAN connections, Ethernet, Broadband, FOOS, and  LTE/4G. If implemented correctly a bandwidth monitor should see the aggregate amount of bandwidth provided by all circuits in the bundle, as well as the performance and utilization on each individual link
  • Line conditioning: Many SD WAN providers will use mechanisms to improve the quality a user will experience. Packet duplication will send duplicate packets down multiple paths in the bundle when the SD WAN detects data loss on circuits, with the thought that one of the duplicates will make it to its destination.
  • Single IP/In call failover: Many providers can offer the benefit of losing a circuit in the bundle without dropping a phone call or a VPN session.
  • Intelligent dynamic traffic steering: When a circuit is showing signs of degradation the SD WAN can steer high priority traffic to better performing links on the fly and revert back when the circuit clears up.
  • Centralized policy control: Because the controller of the SD WAN lives in the cloud, the control and data planes are separated taking processing power needs down on the edges. Policy can be modified and pushed to all devices from a central point easing administration.
  • High Availability and cold spares: These methods for creating redundant hardware arrays are available and are very similar to setting up firewall. VRRP or other protocols are also used for failover.
  • Eliminate the complexities of BGP : SD WAN can eliminate the cost and complexities of BGP configurations.

Potential Disadvantages of SD WAN

Solutions can have their disadvantages, but that is where CTG comes in to help you decide which route your business can take to avoid issues that may occur. We can create an overall solutions based on your business needs, we have the ability to consolidate billing, proactively monitor circuits, work on issues on your behalf and make your experience as seamless as possible.

  • Integration with MPLS: Some SD WAN providers can work MPLS connections and others cannot. Corporate Technologies Group can help you navigate and create the best solution , even a hybrid solution if needed.
  • Core networks: Some SD WAN providers have core networks that can off ramp you to SaaS services and provide similar QoE back to your sites from Internet sources. These networks may also provide a more optimized path than taking a pure Internet path from location to location. The Internet circuits becomes almost like your last mile circuit, particularly when you have private circuits on the backend interconnecting a supplier POPs. This type of design is especially good for large geographical disperse sites, especially when deployed internationally.
  • Gateways: Some SD WAN providers have their own traffic gateways that give the client similar QoS features coming back to the customer as when traffic leaves a site for the Internet.
  • Security: Some SD WAN providers have very little security features and need to work with a firewall provided by the client, while some have very robust security features with next generation firewall capabilities. Other SD WAN providers are now integrating with known firewall providers based on need. Finally, some SD WANs provide their own inherent security and can reliably act as the edge of a network.  For those that don’t provide these types of security functions, work with CTG so that we can create the best of breed solution with hardened security. Contact us for more information on how we can help secure your business.
  • Vendor Involvement: Many vendors could potentially be involved in a solutions, from internet circuits providers, to a different security provider , to an SD WAN provider. We know the different vendors, their strengths and weaknesses, and we can help you decide which ones would be the best options for your business, with CTG being the single point of contact for all providers involved.

How to Execute Your SD-WAN


If not done well, the transition can be painful. For that reason, it is important to plan and execute the whole migration process properly, in order to benefit from the SD-WAN advantages, such as cost reduction, better performance, and increased security. Corporate Technologies Group knows SD WAN and can help you migrate to this solution by doing any of the three options below:

Step Out (Most Common Migration to SD WAN Solution)

You need to start by prioritizing your remote sites and figure out how crucial they are for your whole operation. Then you can start migrating with the sites that are less crucial, this way allows your provider and your technicians to solve any problems if they appear and be better prepared once they set out to incorporate more crucial sites into the system. Once less crucial sites are up and running, you can move important tasks to these sites, while your primary locations are going through migration. This way, your operation does not have to cease at any point.


The flexibility of SDWAN is what draws most enterprises. Therefore, it is a big benefit that you should consider taking advantage of is being able to efficiently utilize both public and private network services. This will bring you reduced WAN costs, simplified management of traffic and devices, better security, and improved visibility. Moreover, a Hybrid SDWAN will allow traffic to flow seamlessly between different links without loss in quality. If one line experiences jitter, latency, or packet loss, another line can take over and meet the agreed SLA.

Rip & Replace

Leased MPLS lines can be quite expensive. Some sites are more crucial than others, so you may have 2 MPLS lines to prevent jitter and packet loss. When transitioning to SD-WAN, if there is a remote site that is not so high on your critical list, you should consider replacing those MPLS lines with cheaper options.  A SD-WAN based solution and a couple of cheap broadband links will give you an equal amount of security but will decrease cost by a large margin. However, another thing to consider here is that broadband options vary from site to site and that in some places the option of multiple carriers does not exist.

Want to learn more about SD WAN? Contact us today and we can find the best solution for your business.