Network Architecture
SD-WAN —
Smarter, faster,
more secure connectivity.
Mergers, acquisitions, new applications, and new business needs make designing and managing an enterprise WAN a never-ending, complicated task — requiring the ability to read minds and predict the future.

With traditional WAN solutions, organizations suffer a less than ideal quality of experience and have a hard time delivering high-performance bandwidth for critical applications. Since legacy WAN architectures rely on packet routing, they lack in-depth application visibility.

Traditional WAN is broken

Traditional WAN was designed based on multiple devices stacked on each other in the branch office, with expensive and limited bandwidth MPLS links connecting them — leading to “data-center dependency” with heavy performance penalties.

Expensive bandwidth
Limited bandwidth of expensive private/MPLS circuits inhibits rollout and impacts performance of applications. Private/MPLS WAN redundancy is complex to deploy and manage.
Datacenter dependent
With no direct access to cloud resources from the branch, traffic is backhauled to the enterprise datacenter with heavy performance penalties.
Unpredictable application performance
Application traffic over internet links lacks SLAs for predictable performance. Every quality of service change requires manual updates across branches and the datacenter.
Complex infrastructure
A multitude of single-function devices and appliances connecting via different WAN links causes infrastructure sprawl and complex branch IT management.

It means complex infrastructure and unpredictable application performance, inability to prioritize, manage and secure — slowing down your business.

Three biggest challenges with the WAN

According to Aryaka’s “State of the WAN” report, time to activate a new site globally is mostly between a week and a month (47% of responses). In 28% of cases it takes more than a month. Slow, expensive, inefficient…

Time to activate a new site globally
What are today’s enterprise WAN requirements?
Enterprise WAN Requirements — by importance
HIGH
MED
LOW
Provide high security
Guarantee reliability and performance (backed by SLAs)
Cope with increasingly high bandwidth / scalability
Improve flexibility — connectivity to cloud services, managing bandwidth requirements (dynamic load balancing, BoD), managing applications’ performance, inserting new services (IoT, surveillance, payment systems)
Provide centralized and automated management for better visibility and reporting / analytics
Faster deployments, especially of new remote sites
Reduce complexity, especially for local branches and remote users
Improve reliability in exotic locations

These requirements — improve security, guarantee reliability and performance, increase bandwidth, improve cloud access, manage application performance, faster deployments and reduce complexity — led to the creation of SD-WAN.

SD-WAN

A Software-defined Wide Area Network (SD-WAN) is a virtual WAN architecture that abstracts software from hardware, creating a virtualized network overlay while using any combination of transport services — including MPLS, LTE and/or broadband.

This overlay intelligently identifies applications on the very first packet and monitors the real-time performance characteristics of the underlying networks. Based on configuration policies, it automatically selects the optimum network for each application.

A simplified and centrally managed SD-WAN architecture lowers both CAPEX and OPEX. Bringing a new branch online is easy and can be done in just a few minutes. No specialized IT expertise is required on premise.

SD-WAN architecture

In technical terms, SD-WAN abstracts the Control Plane from the Data Plane. It reduces recurring network costs, offers network-wide control and visibility, and simplifies technology with zero-touch deployment and centralized management.

SD-WAN architecture — customer portal and path selection
SD-WAN components
  • The SD-WAN edge is where the network endpoints reside — a branch office, remote data center, or cloud platform.
  • The SD-WAN Orchestrator is the virtualized manager, overseeing traffic and applying policy and protocol set by operators.
  • The SD-WAN Controller centralizes management, enabling operators to see the network through a single pane of glass.
SD-WAN components
SD-WAN architecture types
1
On-Premises
SD-WAN hardware resides on-site. Particularly useful for sensitive locations where cloud connection is not needed. The on-site box only connects to your company’s other sites.
2
Cloud Enabled
An on-site SD-WAN box connects to a cloud (virtual) gateway — providing real-time traffic shaping, multi-circuit load balancing/failover, plus increased performance and reliability of cloud applications.
3
Cloud Enabled + Backbone
Your site connects to the SD-WAN provider’s nearest POP, hopping on their private, fiber optic backbone. Traffic is guaranteed low latency, packet loss and jitter. Directly connected to major cloud providers (Office 365, AWS, etc.).
We are in the software era

Traditional WANs based on conventional routers are not cloud-friendly. They require backhauling all traffic from branch offices to a hub data center, impairing application performance. And given that 93% of enterprises have a multi-cloud strategy, this is a critical factor.

Enterprise cloud strategy
Annual public cloud spend
SD-WAN vs MPLS

The ROI of SD-WAN is dramatic and immediate. You can now augment or even replace MPLS connections with broadband internet services to lower WAN costs dramatically.

Requirement MPLS SD-WAN
↑ High importance
Control / reduce ICT costs~
Provide high security~
Guarantee reliability and performance (SLAs)~
Cope with high bandwidth / scalability
Medium importance — Flexibility
Connectivity to cloud services
Managing bandwidth requirements (dynamic load balancing, BoD)
Managing applications’ performance
↓ Lower importance
Centralized and automated management / better visibility
Faster deployments, especially new remote sites
Reduce complexity for local branches and remote users
Improve reliability in exotic locations~
Well / often met    ~ Partially / sometimes met    Not met

SD-WAN makes leveraging different transport methods easy, enabling high-availability configurations that reduce single points of failure. Of course, this doesn’t mean SD-WAN replaces MPLS — it depends on the right usage and specific scenarios.

SD-WAN benefits
  • Increase business productivity and user satisfaction
  • Automatic path selection
  • Improve security and reduce threats
  • Simplify branch WAN architecture
  • Reduce WAN costs
  • End-to-end encryption
  • End-to-end visibility
SD-WAN benefits

Zero-Touch Provisioning (ZTP) — configurations and policies are programmed once and pushed to all branch locations without manual programming. It eliminates the need to send specialized IT resources to branches and reduces human errors.

SD-WAN improves security

Arguably the primary advantage of SD-WAN is security — the prime concern and top requested function for a WAN solution (67% of respondents, SDx Central).

Top functions enterprise want from a WAN solution

SD-WAN has inbuilt security protocols with built-in encryption ensuring only authorized users can access corporate network assets. A company benefits from end-to-end encryption across the entire network, including the Internet.

That leads to a solution called SASE, that unifies SD-WAN, firewall, segmentation, routing, WAN optimization and visibility in a single platform. You can read more about SASE here.

SD-WAN today

Here are the main SD-WAN players in the market, according to the Gartner Magic Quadrant for WAN Edge Infrastructure:

Gartner Magic Quadrant for WAN Edge Infrastructure
SD-WAN predictions

In 2019, the SD-WAN market broke the $1B barrier. IDC’s forecast indicates the market will grow at a 30.8% CAGR from 2018 to 2023 to reach $5.25 billion.

Does your organization have plans to deploy SD-WAN?

Two factors strongly influence interest: cloud usage and digitization, and ICT skills levels. Two main groups have shown most interest:

  • Large enterprises with many small sites (retail, banks) — main attraction: reduce MPLS costs, reduce complexity, achieve faster deployments at the branch
  • Highly digital companies with IT staff and high cloud usage — seeking intelligent, scalable connectivity aligned with their cloud-first strategy