SD-WAN vs. Firewalls: Navigating the Complexities of Network Security

Published on: December 17, 2023

.

19 min read

In the realm of network infrastructure, firewalls and software-defined wide area networking, or SD-WAN, are the two essential components that are crucial for guaranteeing the performance and security of commercial networks. While both perform essential tasks, SD-WAN differs from firewalls in terms of its features and methods of operation.

While firewalls have been the mainstay of network security, SD-WAN is a revolutionary technology that offers better agility, flexibility, and optimization for network management.

Moreover, although they accomplish this in different ways, firewalls and SD-WAN both offer advantages for network administration and security. A firewall enforces rules for the security of incoming and outgoing network traffic, whereas SD-WAN enhances and manages traffic by taking the most effective route. Although many IT professionals utilize these technologies alone, you may combine them for more successful and secure network operation.

You must first understand how firewalls and SD-WANs vary from one another. Understanding the distinction between SD-WAN and firewalls is essential for businesses looking to create reliable, strong networks that can resist the demands of the digital age.

Businesses may ensure that security and performance are adequately handled throughout the design and implementation of their network infrastructures by making informed decisions based on their understanding of the functions and capabilities of firewalls and SD-WAN.

We'll go further into the topics of firewalls and SD-WAN to find the best methods for creating robust and effective networks. Under the following topics, we will look at how SD-WAN and firewalls vary in this article:

• What is SD-WAN
• What is a Firewall?
• What are the Differences between SD-WAN and Firewalls?
  • Purpose
  • Management and Deployment
  • Functionality
  • Security
  • Use Cases

What is SD-WAN?

Software-defined wide area network, or SD-WAN, is a kind of networking technology that optimizes and manages the performance of wide area networks (WANs) by using the concepts of software-defined networking (SDN). SD-WAN improves performance, stability, and scalability and allows enterprises to safely connect people, apps, and data across many locations. Moreover, SD-WAN makes WAN administration easier by offering centralized visibility and control over the whole network.

Through the use of a centralized control function, an SD-WAN may intelligently and securely guide traffic across the WAN to reputable SaaS and IaaS providers. This lowers IT expenses while improving application performance and providing a superior user experience, which boosts company productivity and agility.

By rerouting traffic around WAN connection problems and bottlenecks, SD-WAN guarantees that important data gets to its destination quickly.

Accurate resource allocation and suitable service delivery are made possible by SD-WAN. Through the efficient distribution of traffic across several tunnels, SD-WAN maximizes the usage of network resources, leading to increased system performance and reliability.

What are the Benefits of SD-WAN?

IT can provide routing, threat prevention, cost-effective offloading of costly circuits, and WAN network administration simplicity with SD-WAN. In addition to all of these characteristics, the advantages of SD-WAN are as follows:

• An improved application process
  • Consistent and high availability of services for all essential business applications
  • Several hybrid active-active connections can accommodate all network conditions
  • Application traffic that is dynamically routed using application-aware routing for effective delivery and enhanced user experience
  • improved OpEx, substituting more affordable and adaptable internet (including secure VPN connections) for pricey Multiprotocol Label Switching (MPLS) services,
• Increased safety
  • Rules that are aware of applications and provide real-time access control and end-to-end segmentation
  • Enforcing integrated threat protection at the appropriate location
  • Safe communication into the cloud and across broadband Internet
  • Use NGFW, DNS security, and NGAV to distribute security to the branch and distant endpoints.
• Optimized cloud connectivity
  • Smooth WAN expansion to several public clouds
  • Performance that is tuned in real time for key SaaS programs such as Salesforce and Microsoft Office 365
  • Streamlined processes for cloud computing systems like Microsoft Azure and Amazon Web Services (AWS)
• Streamlined administration
  • A WAN, cloud, and security configuration and management dashboard that is single, centralized, and supplied over the cloud
  • Zero-touch, template-based provisioning for all locations, campus, branch, and cloud
  • Application and WAN performance data, in-depth reporting for business analytics, and bandwidth projections

With the help of a single management tool offered by SD-WAN solutions, network managers may more easily and successfully monitor their networks. IT teams may increase network performance, agility, and user experience while potentially cutting costs if they have more control over the network. SD-WAN systems accomplish these objectives in a variety of ways.

What are the Use Cases of SD-WAN?

The following are seven of SD-WAN's most significant application cases:

1. Connectivity of Branch: The hub-and-spoke architecture of conventional networks, which might impair performance, is not used by SD-WAN systems. Branches, on the other hand, link straight to the cloud or data center, which improves application speed, minimizes overhead, removes bottlenecks, and shortens transit times. Additionally, by allowing branches to select the best network transport for particular kinds of traffic, SD-WAN can hasten connections.
2. Cloud Interaction: The idea that applications are housed in a centralized data center is reflected in traditional WAN topologies. However, this paradigm performs less well when used with cloud apps. SD-WAN offers the most direct path for cloud-based applications by transferring data straight from the branch to the cloud.
3. Safety: One of the primary forces behind the adoption of SD-WAN is security. Organizations may transition to a decentralized security model with the help of SD-WAN's security features, which include application-based firewalls, intrusion prevention, URL filtering, and other unified threat management capabilities. Using these cutting-edge security features, an SD-WAN system can connect branches to cloud-based applications via a secure, direct internet connection, eliminating the need to transport cloud traffic back to a data center for inspection before routing it to the cloud. From the single administration platform, all of these SD-WAN security measures may be controlled and set up.
4. Accessibility to Traffic and Network Operations: Seventy percent of application outages are caused by network problems. Network congestion, packet loss, and failures increase as more people utilize mobile devices, cloud-based services, and bandwidth-intensive apps. With the help of SD-WAN, administrators may quickly identify problems inside the network and take action to address them by having an aerial perspective of the system. When administrators plan for capacity and application priority to enhance the user experience, they may also benefit from this visibility.
5. Quality of Service SLAs and Application Control: With SD-WANs, network administrators can specify service-level agreements (SLAs) for individual applications and make sure that traffic is routed through the network in a way that best satisfies those SLAs. This allows for the routing of some traffic over private circuits and other traffic on more reasonably priced broadband internet circuits, which can reduce networking costs, ease congestion, and enhance application performance, all of which improve the user experience. With SD-WAN, managers may prioritize mission-critical apps in addition to routing traffic via various modes of transportation. Administrators may guarantee that vital applications receive the performance they require by deprioritizing less important apps using application-aware QoS features in SD-WAN systems.
6. The Use of Centralized Administration: With SD-WAN solutions, managers can view the whole network and manage it by simply pushing policies to the branches from a single tool, replacing the separate branch and data center routers that formerly controlled the network. In a few hours, they can even remotely launch additional branches. These safeguards improve and streamline network administration.
7. Adoption of a Cloud-First Approach: Many businesses are moving to the cloud first, and SD-WAN may help with this because it combines all of the above use cases: centralized administration, visibility into network traffic, security, branching and cloud connectivity, and application prioritization. Application hosting in a central data center was the purpose of traditional WAN design. SD-WANs were developed to meet the unique requirements of cloud computing.

What is a Firewall?

A firewall is a type of network security device that keeps an eye on all incoming and outgoing network traffic and uses pre-established security rules to determine whether to allow or prohibit particular types of data. It acts as a gatekeeper between the network within your company and the internet or another network. You can stop illegal users from accessing your network by using a firewall.

Firewalls are the first line of defense in network security and have been for over 25 years. They provide a wall between untrusted external networks, like the Internet, and managed and guarded internal networks that are reliable.

In order to prevent uninvited people from accessing intranets, or private networks linked to the internet, firewalls are frequently utilized.

Firewalls offer vital security against both internal and external threats by guarding the boundary that separates your network from the internet or between certain network segments and the rest of your environment. This is accomplished via firewalls, which filter data in network traffic to shield the system from a wide range of viruses and harmful assaults. Computers and other devices in your network are vulnerable to attack if firewalls aren't installed to stop cyber attacks and prevent unauthorized access.

The purpose of firewalls is to provide a wall between the external world and your internal network. They are a fundamental part of the contemporary corporate network. Firewalls have changed over the last 20 years in order to keep up with more sophisticated assaults and complicated threats. Next firewalls (NGFW) and intrusion prevention features are examples of improvements. Highly specialized appliances that are excellent at analyzing vast volumes of data, identifying the newest ransomware and malware threats, warning against possible Distributed Denial of Service (DDoS) attacks, and assisting companies in meeting increasingly strict compliance requirements are the outcome of these innovations.

Finally, firewalls are critical since they guarantee the security and dependability of your network and shield your sensitive data from hackers. Firewalls are one of the most crucial additions to your tech stack because malicious actors may use them to spread malware and launch distributed denial of service attacks after identifying network weaknesses.

What are the Types of Firewall?

Types of firewalls are listed below:

1. Proxy Firewall: A proxy firewall, an early kind of firewall device, acts as an application's gateway from one network to another. Proxy firewalls block direct connections from outside the network, which allows them to offer extra features like content caching and security. Throughput capacities and the applications they can handle, however, can potentially be impacted by this.

2. Stateful Inspection Firewall: A stateful inspection firewall, now regarded as a "traditional" firewall, permits or prohibits traffic depending on its protocol, state, and port. It keeps an eye on every action, from the moment a link is made until it is broken. Administrator-defined rules and context, which refer to utilizing data from prior connections and packets belonging to the same connection, are the two main factors considered when making filtering judgments.

3. Unified Threat Management (UTM) Firewall: Typically, a UTM device integrates intrusion prevention, antivirus, and stateful inspection firewall capabilities in a loosely connected manner. It could also come with extra services and, frequently, cloud management. UTMs prioritize use and simplicity.

4. Next-Generation Firewall (NGFW): Firewalls are becoming more sophisticated than only stateful inspection and packet filtering. The majority of businesses are installing next-generation firewalls (NGFWs) to thwart modern threats, including application-layer attacks and sophisticated malware. Generally speaking, a next-generation firewall has to have:

   • Stateful inspection combined with intelligence-based access control
   • An integrated method of preventing intrusions (IPS)
   • Control and awareness of applications to identify and prevent dangerous apps
   • Upgrade routes to include upcoming streams of information
   • Methods for dealing with changing security risks
   • Geolocation and reputation-based URL filtering
   • Even though most businesses are starting to require these features, NGFWs are capable of more.
   

5. Virtual Firewall: To monitor and secure traffic across physical and virtual networks, a virtual firewall is typically deployed as a virtual appliance in a public cloud (Amazon Web Services, AWS, Microsoft Azure, Google Cloud Platform, GCP, Oracle Cloud Infrastructure, or OCI) or private cloud (VMware ESXi, Microsoft Hyper-V, KVM). In software-defined networks (SDN), virtual firewalls are frequently essential elements.

6. Cloud-Native Firewall: Applications and workload infrastructure may have been fully protected at scale thanks to cloud-native firewalls. Cloud-native firewalls allow networking operations and security operations teams to operate at fast speeds thanks to automatic scaling features.

What are the Differences Between SD-WAN and Firewalls?

The purpose of firewalls is to provide a wall between the external world and your internal network. They are an essential component of the contemporary corporate infrastructure network. Firewalls have changed over the last 20 years to keep up with the rapid advancement of sophisticated assaults and complicated threats. The purpose of managed SD-WAN solutions is to link companies with the external environment. Businesses now need to ensure and maximize Internet connections as more corporate apps shift to the cloud.

By utilizing functions like load balancing, software-defined wide area networking (SD-WAN), automated failback and failover, QoS, or quality of service, performance measurements and alerts, and load balancing, the solutions maximize connection performance and prevent outages. Through the consolidation of several network tasks into a single platform, the SD-WAN managed services further streamline network operations. The elimination of the need for separate appliances due to integrated security services, load balancing, traffic shaping, and WAN optimization lowers hardware and operating expenses.

Firewalls are crucial for perimeter security, but in order to handle the increasing threats, they require more security equipment, which increases maintenance and upfront expenses.

The key distinctions between firewalls and managed SD-WAN are given in the following table:

Criteria	SD-WAN	Firewalls
Purpose	It provides enhanced performance, dependability, and scalability while enabling organizations to securely connect users, applications, and data across multiple locations.	The purpose of a firewall is to stop illegal users from entering or leaving a computer network.
Management and Deployment	Two of the main benefits of managed SD-WAN are scalability and centralized administration.Because SD-WAN devices are sent to branch locations already configured, setup is quick and easy.	An important limitation of scalability is the lack of centralized control. Each firewall device might need to be manually configured, which can be time-consuming at times and is more common in companies with several branch offices or a dispersed network design.
Functionality	Managed SD-WAN enables businesses to manage their networks with unmatched agility and flexibility.	A firewall's ability to precisely manage bandwidth allocation is limited.
Security	A more sophisticated security solution that tackles the ever-changing risks of the modern world is provided by SD-WAN.	Firewalls are still a crucial component of any security configuration, controlled.
High availability and hot failover	By providing automatic failover capabilities, lowering the possibility of human error, and guaranteeing increased availability without sacrificing security, managed SD-WAN streamlines the procedure.	Network administrators have to manually install and manage the error-prone and time-consuming failover methods in the firewall-based architecture.

Table 1. SD-WAN vs. Firewalls

Purpose

Although they accomplish it in different ways, firewalls and SD-WAN have the same goal of offering network security and administration advantages. Incoming and outgoing network traffic security is governed by rules that a firewall enforces, whereas traffic is enhanced and managed by SD-WAN, which routes it via the most efficient path. Although many IT professionals utilize these technologies alone, you may combine them for more successful and secure network operation. If we look at each of their individual goals, they are as follows:

SD-WAN is becoming more and more important as organizations depend more and more on internet access for cloud and business-critical apps. The goal of SD-WAN is to lower operating costs and complexity while increasing uptime and business agility. Moreover, SD-WAN simplifies management by providing a single dashboard that enables companies to grow and manage branch networks. It gives you the freedom to link any carrier-independent WAN to boost bandwidth availability and dependable connections at a reasonable price.

In addition to all of the above, SD-WAN is made to address the many problems that come with traditional WAN, providing networking experts with an easier approach to maximize and secure WAN connectivity. SD-WAN is designed to manage various traffic types and situations in real-time, with a software-based foundation as opposed to a hardware one. Compared to traditional WANs, it offers superior security and dependability and can swiftly adjust to changing circumstances.

On the other hand, the purpose of a firewall is to stop illegal users from entering or leaving a computer network. In order to prevent uninvited people from accessing intranets, or private networks linked to the internet, firewalls are frequently utilized.

Specifically, firewalls offer vital defense against both internal and external threats by guarding the boundary that separates your network from the internet or between certain network parts and the rest of your environment. This is accomplished via firewalls, which filter data in network traffic to shield the system from a wide range of viruses and harmful assaults. Computers and other devices in your network are vulnerable to attack if firewalls aren't installed to stop cyber attacks and prevent unauthorized access.

Management and Deployment

Scalability and centralized management are two of managed SD-WAN's key advantages. When companies expand, establish new locations, or utilize cloud-based software, the network needs to promptly adjust to these auxiliary modifications.

With SD-WAN, businesses can quickly add or delete network resources thanks to its seamless scalability. IT managers can effectively set network policy, monitor performance, and execute changes across the whole network through a single interface thanks to managed SD-WAN's centralized management dashboard.

However, the manual configuration of firewalls for each device or location would result in increased complexity and time-consuming job management. The absence of centralized control would hinder scalability, resulting in inconsistent network security rules and making it more challenging to maintain consistent security measures across various network segments.

Additionally, managed SD-WAN solutions cut down on the time and effort required to set up and maintain the network infrastructure by being made for quick deployment and easy maintenance. SD-WAN devices provide simple and rapid deployment by being sent to branch sites.

Additionally, centralized administration consoles simplify ongoing maintenance work and allow for remote settings, firmware upgrades, and policy changes.

On the other hand, the deployment and management of firewalls are frequently difficult procedures. Every firewall device may require a manual configuration, which is sometimes laborious and is especially true for businesses with a spread network architecture or several branch offices.

By reducing the complexity of deployment and centralizing administration, managed SD-WAN frees up IT teams to concentrate on strategic projects rather than devoting a significant amount of time to network maintenance.

Functionality

Businesses can manage their networks with greater flexibility and unparalleled agility thanks to managed SD-WAN. Unlike firewalls, which primarily focus on perimeter security, SD-WAN uses software-defined networking to optimize and streamline network traffic.

Using SD-WAN network resources, companies can change the path of traffic based on real-time connections, like available bandwidth and network congestion. This makes applications that use a lot of bandwidth less of a problem and makes sure that all types of network traffic run smoothly. This feature guarantees that critical apps receive more attention, which improves speed and reduces latency. SD-WAN automatically optimizes and manages bandwidth utilization to improve the user experience and network efficiency.

Moreover, managed SD-WAN provides built-in support for cellular, internet, and MPLS networks, among other connections. Businesses may employ more affordable internet lines while still retaining secure connectivity, thanks to the increased flexibility. On the other hand, firewalls are not able to handle a variety of connection types because their primary purpose is to safeguard specific network components.

Despite being necessary for network security, firewalls do not have precise control over how much bandwidth is allotted. Their primary goal is to implement security policies, but, depending on the demands of the application, they may also require systems to prioritize or optimize network traffic.

Aside from all of this, SD-WAN's capabilities guarantee that VoIP and real-time video conferencing, two business-critical applications, get the network resources they need to improve the user experience and productivity.

Security

While firewalls remain an essential part of any security setup, managed SD-WAN offers a more advanced security solution that addresses the dynamic threats of the modern world.

The managed SD-WAN's integrated security capabilities, which include sophisticated threat detection, encryption, and authentication, secure the traffic across the application tiers. Modern security is guaranteed throughout the network, including data centers, cloud environments, and branch offices.

Moreover, integrated security services like intrusion prevention systems, secure web gateways, and data loss prevention technologies are included in managed SD-WAN solutions. These SD-WAN security capabilities provide their companies with a unified approach to network security, doing away with the need for complicated setups or specific security equipment.

Even though firewalls are good at protecting specific segments, an SD-WAN that is properly managed offers more comprehensive security capabilities than any firewall can match.

High Availability and Hot Failover

Managed SD-WAN ensures continuous connection and business continuity by providing strong failover and high availability techniques. In the event of a network breakdown, hot failover primarily refers to the device's or the backup connection's smooth and automatic transition.

In order to continuously guarantee the network's availability, businesses can set up redundant connections, such as numerous internet lines or different carriers. The SD-WAN system can quickly and automatically divert traffic to the backup connection in the event that the primary link fails, minimizing downtime and preserving uninterrupted connectivity.

Firewalls are essential for maintaining network security, but they typically lack built-in failover capabilities. Network administrators have to manually install and manage the error-prone and time-consuming failover methods in the firewall-based architecture.

By providing automatic failover capabilities, lowering the possibility of human error, and guaranteeing increased availability without sacrificing security, managed SD-WAN streamlines the procedure.

Integrating Firewalls and SD-WAN

Despite their numerous differences, firewalls, and SD-WAN can operate better together to enhance network administration, security, and performance. By doing this, you can guarantee that the apps you use run properly and stop cyberattacks.

You may concentrate on other IT responsibilities by streamlining network administration by integrating firewalls with SD-WAN. A centralized network management solution can help you by lowering component failure rates and guaranteeing availability.

Integrating SD-WAN with a firewall is a multi-step process. The first step is to identify the security and performance needs of your network and select a firewall that can function with an SD-WAN device. After that, you must physically attach your preferred firewall to the gadget and set up the firewall's security settings. This assists you in selecting which network traffic to allow or prohibit. You must ascertain the SD-WAN device's network optimization protocols.