How Are Firewalls and SD-WAN Related?

5 min. read

SD-WAN (software-defined wide area network) and firewalls are related through the integration of firewall capabilities in secure SD-WAN solutions.

While SD-WAN optimizes and manages WAN connections for better performance and cost savings, integrated firewalls ensure traffic is secure by monitoring and controlling it according to predefined security policies.

Combining SD-WAN and firewalls allows organizations to efficiently manage and secure their network traffic through a single solution. This provides both optimized performance and robust protection against threats.

What is SD-WAN?

SD-WAN  Architecture Explained

SD-WAN (software-defined wide area network) is a technology that uses software-defined networking (SDN) principles to manage and optimize wide area networks (WANs). It allows organizations to securely connect users, applications, and data across multiple locations. SD-WAN also enhances application performance, connection reliability, and network scalability.

SD-WAN operates as a virtualized service that extends enterprise networks over large geographical distances. It uses links such as multiprotocol label switching (MPLS), wireless, broadband, virtual private networks (VPNs), and the internet.

This setup allows users who are working in branch and remote locations to efficiently access corporate applications and resources–no matter where they are. By monitoring WAN connection performance and managing traffic, SD-WAN maintains high speeds and optimizes connectivity. The end result is a far better user experience for employees.

The architecture of SD-WAN includes a centralized control plane that routes traffic and allows network admins to deploy rules and policies across the entire network at the same time. The detachment of control from hardware simplifies network management and enhances service delivery.

SD-WAN appliances follow operational guidelines set by the central controller. This majorly reduces the need to manage gateways and routers individually.

SD-WAN Components

SD-WAN gateways support hybrid WAN, which gives each branch appliance the ability to maintain multiple connections through various transport methods. By using different connection types interchangeably, SD-WAN increases network bandwidth, performance, and redundancy.

Ultimately, SD-WAN solutions facilitate centralized management and reduce the need for individual gateway and router management.

What is a firewall?

How Firewalls Work

A firewall is a network security solution that monitors and regulates traffic based on defined security rules. It acts as a barrier between private and external networks, checking and filtering data to decide if it should be allowed, blocked, or dropped.

This process ensures only safe, legitimate traffic gains entry, which protects the network from potential threats. Firewalls can be implemented within network architecture as hardware, software, or a combination of both.

What is the role of a firewall in network security?

Firewalls play a crucial role in network security by serving as the first line of defense.

By monitoring and controlling traffic, a firewall helps prevent unauthorized access, cyber attacks, and the spread of malware.

The process protects the organization's digital assets, maintains data integrity, and ensures the overall security of the network infrastructure.

This ensures the digital safety of an organization's assets and data.

What is secure SD-WAN?

The term "secure SD-WAN" refers to an SD-WAN solution that incorporates advanced security services and features alongside its primary function: optimizing and managing wide area network (WAN) connections.

While traditional SD-WAN focuses on enhancing network performance and connectivity, secure SD-WAN goes a step further by integrating robust security measures to protect against cyber threats.

Secure SD-WAN combines the benefits of traditional SD-WAN with comprehensive security features, including but not limited to:

The goal is to provide a holistic solution that optimizes network traffic and protects against a wide range of cyber threats.

The evolution from traditional SD-WAN to secure SD-WAN is driven by the increasing complexity and sophistication of cyber threats. As organizations rely more on cloud applications and services, in addition to direct internet access, the need for enhanced security becomes critical.

Secure SD-WAN addresses this need by integrating advanced security features. It provides a unified solution that ensures both optimal network performance and robust protection.

Further reading: What Is SD-WAN Multicloud?

What is the role of firewalls in secure SD-WAN?

Firewalls play a crucial role in securing SD-WAN deployments by providing advanced security features integrated into the network fabric.

In secure SD-WAN architectures, NGFWs are deployed at branch locations and headquarters, serving as a first line of defense against cyber threats.

NGFWs are virtualized versions of traditional firewalls, offering enhanced capabilities including but not limited to:

A key function of NGFWs in secure SD-WAN is to enforce security policies consistently across all locations. This maintains the same level of security, whether users are accessing data from a branch office, headquarters, or through cloud based services.

By integrating NGFWs with SD-WAN, organizations benefit from centralized management. Centralized management substantially simplifies the time consuming task of deploying and managing security policies.

Plus, the integration helps reduce the potential for misconfigurations that can often crop up when network admins are managing separate networking and security devices.

Secure SD-WAN Deployment

Another role of firewalls in secure SD-WAN is traffic segmentation and encryption. NGFWs inspect and filter traffic based on predefined security rules. Which ensures only legitimate, safe traffic can pass through.

NGFWs also decrypt and inspect SSL/TLS traffic to detect and block threats hidden in encrypted data. This is an essential capability for maintaining robust security in environments where encrypted traffic is increasingly common.

Next-Generation Firewall

Then there’s the fact that firewalls contribute to the zero-trust architecture of secure SD-WAN.

In a zero-trust model, all traffic is verified before it is allowed to access network resources, regardless of origin.

NGFWs support zero trust because they inspect and authenticate all network traffic. This establishes granular control over who can access what resources. And that prevents unauthorized access and lateral movement of threats within the network.

Not to mention, NGFWs in secure SD-WAN environments support advanced threat detection and response to identify and mitigate cyber threats in real-time.

These are all essential security capabilities for protecting the network against sophisticated attacks and ensuring the overall security of the SD-WAN deployment.

SD-WAN and firewalls FAQs

No, SD-WAN is not the same as a firewall. SD-WAN is a networking technology that manages WAN connections, while a firewall is a security device that monitors and controls network traffic.
Firewalls in SD-WAN provide security by filtering traffic, detecting intrusions, and enforcing policies to protect against cyber threats.
A firewall is not primarily a WAN device; it is a network security device that can be deployed in various network locations, including within a WAN.
An SD firewall, often part of SD-WAN, combines traditional firewall functions with software-defined networking principles for enhanced security and manageability.
SD-WAN improves security by integrating features like encryption, secure tunneling, and advanced firewalls, providing centralized policy enforcement and threat detection across the network.