SD-WAN Solutions for Business Networks

SD-WAN (Software-Defined Wide Area Network) is not just a more modern version of a site-to-site VPN. It is an architecture that brings intelligent traffic management at the application layer (Layer 7 of the OSI model) — meaning the network knows the difference between a VoIP call, an ERP session, and a video stream, and treats them differently, automatically.

For companies with multiple sites, remote workers, or cloud-dependent services, SD-WAN delivers the stability, visibility, and control that traditional WAN architectures could only achieve with expensive MPLS links. Codex Media designs and implements SD-WAN solutions with a focus on high availability, security, and operational simplicity.

What it means in practice

multiple office locations in a single logical network with central management
automatic failover between multiple uplinks (fiber, 4G/5G, cable)
QoS policies that prioritize business-critical applications
Layer 7 traffic identification — the network knows which app uses which link
traffic segmentation between sites without manual per-device ACLs
real-time visibility: which user, which app, how much bandwidth
centralized configuration without SSH-ing into each device individually

Layer 7 segmentation — why it matters

Traditional QoS operates at the IP address and port level (Layer 3/4). SD-WAN works at the application layer (Layer 7) — meaning it can identify Zoom, Microsoft Teams, SAP, or your own ERP system regardless of which port it uses.

In practice: when an internet link becomes saturated, SD-WAN automatically steers VoIP traffic to the better path, throttles video streaming sessions, and gives ERP communication priority — all without IT intervention and without service interruption.

Problems it solves

unstable or slow inter-site links
no failover — when a link drops, everything stops
complex management of distributed network infrastructure
critical apps slower than streaming services on the same connection
high MPLS link costs between locations
no visibility into who consumes bandwidth and for what
IT team spending hours manually configuring each router

Technologies and approaches

SD-WAN controllers (cloud-managed or on-premise)
edge devices at each location
IPsec/TLS overlay tunnels between sites
dual/multi-WAN with active load-balancing logic
VLAN segmentation and micro-segmentation
Application-Aware Routing policies
integration with existing firewall and security stack

Typical scenarios

Retail chain with 10+ stores

Each store has a local ISP. The central ERP and POS system must always be available. We implement SD-WAN with dual-WAN (fiber + 4G backup) at each location, centralized policy management, and automatic failover that ensures the checkout system is never offline — even when the primary link fails.

Office migrating from MPLS to SD-WAN

The company pays for expensive MPLS links that no longer provide sufficient throughput for cloud services. We migrate to an SD-WAN overlay combining local internet connections while maintaining service quality and security. The result is lower link costs with better performance for cloud applications.

Company with field vehicles and mobile offices

Field workers need secure access to internal systems over 4G/5G. We integrate mobile clients into the SD-WAN architecture, ensure encrypted traffic toward the central cloud, and set policies that limit bandwidth for non-critical traffic when on cellular connections.

How we approach implementation

We start with an analysis of the existing WAN infrastructure — mapping sites, links, applications in use, and availability requirements. Based on that, we design an SD-WAN architecture that fits actual needs — not a vendor template.

Migration is planned site by site, with the ability to run old and new infrastructure in parallel until everything is verified. After rollout, we deliver documentation and brief the people responsible for IT so they can manage policies independently going forward.

Frequently asked questions

What is the difference between SD-WAN and a classic site-to-site VPN?

A classic site-to-site VPN creates a secure tunnel between two locations but has no intelligence — all traffic is treated equally, without prioritization or application visibility. SD-WAN adds a management layer that understands traffic at the application level (Layer 7), can automatically steer traffic across multiple links depending on link quality and application needs, and is managed centrally rather than device by device.

How many sites do I need for SD-WAN to make sense?

The benefit starts at two sites if you have critical systems that require high availability. For application QoS and Layer 7 management, it is useful even for a single site with multiple uplink connections. The typical sweet spot is companies with 3 or more locations — but this is not a hard rule. We always make the decision together based on an analysis of your actual situation.

Can SD-WAN replace the MPLS link I currently have?

In most cases, yes — SD-WAN can replace MPLS using standard internet connections (fiber, cable, 4G/5G) while maintaining an equivalent or better level of reliability and security. The added benefit is significantly lower link costs and better throughput for cloud services. Migration is planned gradually to avoid service disruption.

What happens when a link goes down?

Automatic failover — SD-WAN detects link degradation within seconds and shifts traffic to the available path, without users noticing an interruption for critical applications. VoIP calls remain active, ERP sessions are not dropped, VPN tunnels are rebuilt automatically. Failover thresholds are configured to your specific applications and requirements.

Is SD-WAN secure — can data be intercepted?

All traffic between sites is encrypted through IPsec or TLS tunnels — the same level of protection as a traditional VPN, with the added benefit of centralized management and visibility. For an additional security layer, we integrate SD-WAN with network firewall systems and segmentation policies.

How long does deployment take?

For a typical 3–5 site implementation — from analysis to production, usually 2 to 4 weeks. Each site is migrated in a separate window, with the option for a fast rollback if anything does not go as planned. Larger implementations with more than 10 sites are planned in phases.

Related services

Network security & firewall·Cloud centralization·VPN & remote access·Security audit

Request an assessment

Tell us about your situation — number of sites, types of connections you have, which applications are business-critical. No standard offers, just a concrete analysis and a proposal that makes sense for your business.