Large companies rarely operate out of a single office: dozens or hundreds of locations — offices, warehouses, retail sites, production facilities — need to be connected so they function as a single infrastructure. For a long time, MPLS was the standard for this. Today it's increasingly being replaced or complemented by SD-WAN — software-defined wide area networks.
In this article, we look at what Secure SD-WAN is, how it differs from classic SD-WAN, and why business needs it.
What Is SD-WAN
SD-WAN (Software-Defined Wide Area Network) is an approach to building corporate networks in which traffic management is decoupled from the physical communication channels. Instead of rigidly routing packets over a single dedicated channel, SD-WAN intelligently distributes traffic across several available channels — internet, LTE/5G, MPLS.
The SD-WAN controller tracks the state of each channel in real time: latency, packet loss, load. Based on this data, it automatically routes different types of traffic along the optimal path: video calls over the lowest-latency channel, background synchronization over a cheaper one.
Centralized management from a single console is one of the main arguments for SD-WAN. Instead of manually configuring a router in every office, an administrator manages policies for the entire network from one place.
Problems SD-WAN Solves
High cost of MPLS. Dedicated MPLS channels are expensive, and the cost grows in proportion to the number of sites and traffic volume. SD-WAN shifts part of the load to cheaper channels — internet or mobile connectivity.
Slow rollout of new sites. Connecting a new office to MPLS takes weeks or months. SD-WAN deploys faster: a device at the new site registers itself with the central controller automatically — this is called Zero Touch Provisioning.
Inefficient cloud traffic. In a traditional architecture, traffic from an office to SaaS applications routes through the central data center — the "hairpinning" effect. SD-WAN opens a direct path to the cloud from every site, cutting latency and offloading the central channel.
No redundancy. If the single MPLS channel goes down, the office loses connectivity. SD-WAN automatically fails over to a backup channel without administrator intervention.
Security at the Perimeter of Every Branch
Classic SD-WAN optimizes traffic but doesn't protect it. As soon as an office gets a direct path to the internet, every site becomes a potential entry point for an attacker. Secure SD-WAN solves this: it combines SD-WAN capabilities with built-in network security functions — at the perimeter of every branch, not just in the central data center.
Secure SD-WAN includes:
Next-generation firewall (NGFW). Traffic inspection, application control, intrusion prevention — right on the device in the office, without sending traffic to the center for analysis.
IPS/IDS. Detection and prevention of network attacks at the perimeter of every site.
Web filtering. Control over access to web resources, protection against phishing and malicious sites.
Traffic encryption. All traffic between points of presence is encrypted.
Traffic segmentation. Corporate traffic, guest Wi-Fi, and IoT devices are isolated at the branch device — without needing to route traffic to the central data center for separation.
BI.ZONE Secure SD-WAN
BI.ZONE Secure SD-WAN is a Russian Secure SD-WAN solution for the enterprise segment. It combines traffic routing and load balancing with network security functions in a single device for each point of presence.
The solution suits organizations with an extensive branch network that need to manage the network centrally, control security at every perimeter, and reduce dependence on expensive dedicated channels.
Comparing MPLS, SD-WAN, and Secure SD-WAN
| Parameter | MPLS | SD-WAN | Secure SD-WAN |
|---|---|---|---|
| Traffic management | Centralized, rigid | Dynamic, multi-channel | Dynamic, multi-channel |
| Cost | High | Lower (internet + backup) | Lower (internet + backup) |
| Built-in security | None | None or basic | NGFW, IPS, filtering |
| Speed of connecting a new site | Weeks-months | Days (ZTP) | Days (ZTP) |
| Direct cloud access | No | Yes | Yes |
| Traffic segmentation | Limited | Basic | Flexible, at the perimeter |
| Channel redundancy | Requires additional contracts | Automatic | Automatic |
Which Organizations Benefit from Secure SD-WAN
Secure SD-WAN is especially useful if:
- the company has several offices, stores, or production sites;
- part of the traffic goes to SaaS services or public clouds;
- the company wants to cut spending on dedicated channels;
- regulatory requirements mandate data protection at the level of every branch;
- the current network can't keep up with growing load.
For small companies with a single office and simple infrastructure, Secure SD-WAN is likely overkill. But as the company scales, it's a question worth studying ahead of time — not once the infrastructure is already on fire.
Frequently Asked Questions
How Does Secure SD-WAN Differ from SASE?
SASE (Secure Access Service Edge) is a broader concept that combines SD-WAN with cloud-delivered security functions (ZTNA, CASB, FWaaS, and others) provided as a service. Secure SD-WAN is closer to an on-premises or hybrid model with devices at every site. SASE is built on the cloud. They overlap, but they solve problems of different scale and with different operating models.
Do We Need to Replace the Routers in Our Offices?
When moving to SD-WAN, an SD-WAN device is installed at each site and takes over the functions of the router and security gateway. Existing routers can remain in place as transport, but they won't get full traffic management through the SD-WAN controller.
Can We Keep MPLS When Moving to SD-WAN?
Yes. A typical architecture keeps MPLS for critical traffic — ERP systems, for example — and uses internet channels for lower-priority traffic and SaaS. SD-WAN automatically distributes flows across the available channels.
How Does SD-WAN Affect Latency for Users?
With the right configuration, latency drops — especially for cloud traffic, which no longer routes through the central data center. SD-WAN's QoS policies ensure critical applications get priority in the queue.
How Does Secure SD-WAN Help Meet Regulatory Requirements?
Built-in encryption, traffic segmentation, and logging at the level of every device make it easier to meet data protection requirements and audit network activity — without needing to route all traffic to the central data center for inspection.
Hands-On Practice at BI.ZONE Cybersecurity Labs
The Sales Specialist for BI.ZONE Secure SD-WAN course on the BI.ZONE Cybersecurity Labs platform covers the product's architecture and key application scenarios. Participants work on real test benches, configure routing and security policies, and gain hands-on experience that's hard to get from theory alone.