Why SD-WAN?

Traditional WANs use a centralized architecture, routing all branch traffic through the data center for internal applications and internet access. While effective in the past, this model struggles with today’s cloud- and SaaS-heavy environments, causing delays and packet loss — a challenge known as traffic trombone.

SD-WAN addresses this by enabling the use of multiple transport types, offering centralized, programmable control that’s decoupled from hardware. It improves traffic steering for better application performance and SLA adherence, and is delivered as a flexible, subscription-based Network-as-a-Service (NaaS) model.

Benefits of SD-WAN

Edge-to-edge network security and micro-segmentation.

Improved application performance. Provide better application experience regardless of where the application resides.

Highly adaptable to custom and 3rd party products

Assure business-critical with advanced application visibility and control

It improves business agility and responsiveness and reduces complexity

More Bandwidth for Lower Cost which results in lower OpEx and CapEx

Why and When MPLS VPN Deployed?

• Business applications such as ERP, Citrix, VoIP, Video NEED Predictable and quality network services
• Secure Connectivity among Multiple branch offices - Users, Systems & applications
• Financial impact of poor WAN quality or down time more in Consumer businesses or org. that deal with higher volume of transactions.

Industry Standard For SD-WAN

There is no universal industry definition for SD-WAN, but most solutions combine traditional WAN features like VPN, IPsec, hybrid WAN, QoS, and analytics with modern technologies such as SDN, NFV, and service orchestration. These enable dynamic, policy-based traffic routing and faster service deployment.

SD-WAN Managed Services use overlay networks to deliver secure, agile, and application-aware connectivity, making them a key part of the MEF Third Network vision.

According to MEF 70, SD-WAN is an application-aware, over-the-top WAN service that intelligently routes traffic across multiple underlay networks, regardless of the provider or technology.

SD-WAN Architecture and How it Works

Components of SD-WAN architectures as below:

• Centralized Orchestrator (typically cloud based & Multi-tenant) Centralized management of SD-WAN edges & gateway
• SD-WAN Edge with zero or low touch provisioning (deployed in branch premises)
• Cloud services Gateway (Optional - Multi-tenant Services Edge)

Device On-Boarding & Security

• Each SD-WAN device is pre-assigned a unique ID and secret key by the orchestrator.
• Devices authenticate using hardware fingerprints and receive an RSA certificate.
• Upon registration, a secure management tunnel is established, and traffic, tunnel, and QoS policies are pushed.

Core Features of SD-WAN

• Unified Transport: Multiple active WAN links with dynamic link quality assessment.
• Smart Traffic Steering: Application-based routing and multi-path bonding.
• Integrated Security: Scalable VPN and basic UTM features.
• Centralized Orchestration: Simplifies operations and service management.
• Flexible Deployment: Physical or virtual SD-WAN edges.
• Service Orchestration: Full lifecycle management for SD-WAN and related services.
• Subscriber Portal: Enables easy service ordering and modification.

SD-WAN or Traditional WAN?

The SD-WAN market is rapidly expanding, with a Forrester study showing that over 64% of U.S. companies are planning to adopt SD-WAN solutions. While traditional WAN remains a dependable option, many businesses find a hybrid approach—leveraging both—offers the best balance of performance and cost-efficiency.

Traditional WAN relies on MPLS, routers, and VPNs to connect branch offices via centralized infrastructure. It offers strong security and quality of service but can be costly and less scalable due to manual provisioning.

SD-WAN, on the other hand, integrates broadband, LTE, and MPLS to deliver flexible, cloud-ready connectivity. It enhances control, reduces costs, and supports secure, encrypted communications with easier scalability and remote deployment.

Traditional WAN

VS

SD-WAN

How Does SD-WAN Provide You With Network Security?

Most SD-WAN solutions provide robust encryption and network security through key technologies such as IPsec, VPN tunnels, firewalls, and application traffic microsegmentation. These features secure branch-to-branch data transmission and protect sensitive information across the network.

While IPsec has become a standard among SD-WAN vendors, it's important to recognize that true network security extends beyond encryption. SD-WAN enhances agility and reduces operational costs (Opex), but organizations must not compromise security for lower capital expenditures (Capex).

To address modern threats while managing costs, businesses are increasingly virtualizing security functions within SD-WAN. This approach allows for flexible, scalable protection without the need for constant hardware upgrades—ensuring both security and efficiency in today’s dynamic IT environments

SD-WAN uses virtual machines, which helps organisations to install updates on existing hardwares, rather than doing it manually which incurs CapEx and time.

What is SDN and How it Differs from SD-WAN?

What is SDN and How it Differs from SD-WAN?

MPLS (Multiprotocol Label Switching)

Advantages:

• High reliability and consistent packet delivery
• Excellent Quality of Service (QoS)
• Traffic prioritization for critical applications

Disadvantages:

• High bandwidth costs, especially for modern data-heavy applications (e.g., VR, video)
• Limited scalability and flexibility
• No built-in encryption, increasing vulnerability if misconfigured

SD-WAN (Software-Defined Wide Area Network)

Advantages:

• Cost-effective and scalable with no bandwidth penalties
• Enhanced visibility, control, and performance
• Supports hybrid connectivity (e.g., broadband, LTE)
• Integrated security, policy management, and orchestration

Disadvantages:

• May not match MPLS for real-time traffic reliability in some cases
• Dependent on internet quality for performance

While MPLS offers superior reliability, SD-WAN delivers greater flexibility, cost savings, and built-in security—making it a strategic choice for modern, cloud-first businesses. Organizations should evaluate both based on performance needs, cost constraints, and future scalability.

SD-WAN vs VPN

VPN is like a manual gearbox in your car. SD-WAN is like an automatic gearbox with radar-guided cruise control. Both achieve the same result (connectivity between 2 remote locations), but SD-WAN hides away from you lots of complexity with building redundant tunnels, monitoring the quality of the tunnels and failing over.”

Ultimately, SD-WAN is a collection of technologies, packaged together with a nice GUI that make managing VPN connectivity between remote locations MUCH easier.

SD-WAN leverages multiple active WAN links / Paths and delivers secure & superior connectivity between branches/DC/Cloud through directly programmable data plane

SD-WAN vs DMVPN

Dynamic Multipoint VPN is an evolution of IPSec tunnels which is primarily site to site tunnels. For IPSec tunnels, both the client and the IPSec Gateway have to be individually configured for secure communications.

This configuration has to be repeated with each IPSec client & at the Gateway added to the VPN. This is more time consuming, cumber-some and error-prone. Also, VPN tunnels don't scale.

DMVPN leverages new features such as NHRP, mGRE along with IPSec to dynamically create mesh VPN to other spokes.

SD-WAN vs WAN Optimization

Deduplication, where the WAN substitutes a kind of shorthand for well-known data patterns to avoid having to send the actual data across the link. Basic quality-of-service (QoS) to prioritize traffic from some applications over others. Blocking to prevent unwanted traffic from consuming valuable bandwidth. Forward error correction (FEC) to account for packet loss.

Deduplication, where the WAN substitutes a kind of shorthand for well-known data patterns to avoid having to send the actual data across the link. Basic quality-of-service (QoS) to prioritize traffic from some applications over others. Blocking to prevent unwanted traffic from consuming valuable bandwidth. Forward error correction (FEC) to account for packet loss.

Deduplication, where the WAN substitutes a kind of shorthand for well-known data patterns to avoid having to send the actual data across the link. Basic quality-of-service (QoS) to prioritize traffic from some applications over others. Blocking to prevent unwanted traffic from consuming valuable bandwidth. Forward error correction (FEC) to account for packet loss.

Unlike wan optimization which does not delay sensitive traffic systems, sd-wan is pre inclined towards real-time networking, accounting for jitter, latency and packet loss to check traffic is at optimal conditions across your WAN.

It can surprisingly increase your organization's visibility into private or public (or both) applications, to provide you more control and ensure resilience and agility.

Why Does Your Company Need SD-WAN?

Switching to sd-wan (software-defined wide area network) allows organizations to connect all their network supplies and visibilities. This allows organizations to use their cloud-based technology, with no or minimal expensive hardware. Thus, it helps businesses to decrease CapEx and Opex.

SD-WAN for organization provides :

• Integrated security function
• Virtual overlay network
• Application and network activity monitoring
• Control and management infrastructure

What you need to consider before choosing your new SD-WAN Vendor?

Here are some important questions that you should consider before selecting your vendor. You must ensure that the vendor can fulfill your current needs and future needs as well.

• Does the vendor guarantee you predictable performance of your application platforms?
• Can your vendor support new and customized applications?
• Is the SD-WAN compatible with integrated wan optimization at various company branches?
• How will the connection interact with current routers, gateways, and firewalls?
• Does your vendor provide you with a centralized orchestration console, for your organizational use in managing application QoS and network security?

What are SD-WAN Takeaways?

• SD-WAN is a wide area network with virtual connectivity, which uses software and minimal use of hardware
• Its architecture works cloud-based, which makes it highly suitable for scaling up
• Its architecture works cloud-based, which makes it highly suitable for scaling up
• Highly simplified network connectivity, resilient, and agile service