SASE vs Firewall: Differences in Security and Deployment

Published on: October 14, 2024

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14 min read

Secure Access Service Edge (SASE) and traditional firewalls represent two distinct approaches to network security. They are both essential components of network security, but they serve distinct purposes and offer different levels of protection. Understanding their differences in security capabilities and deployment models is crucial and very beneficial. The main goal of SASE is integrated security and networking. SASE combines security functions such as Secure Web Gateways (SWG), Zero Trust Network Access (ZTNA), and Cloud Access Security Brokers (CASB) with software-defined wide-area networking (SD-WAN) capabilities. This integration allows for consistent security policies applied across diverse environments. It aims to safely access data and applications in diverse and distributed network structures. Another goal of SASE is to provide a decentralized security perimeter.

Unlike traditional firewalls that secure a defined perimeter, SASE goes with a decentralized approach. It tends to inspect traffic at the nearest points of presence (PoPs). This model comes with responsiveness and reduces latency for remote users. SASE employs AI and machine learning to dynamically adapt to changing security threats. SASE provides a comprehensive security solution that extends beyond perimeter protection. It encapsulates network access control, threat prevention, data protection, and more. It offers integration with various security tools and services. SASE solutions are exclusively delivered via the cloud. This helps to scale security services efficiently without the need for extensive hardware. This model simplifies management and allows for quick adaptation to changing business requirements. The unified management mentality reduces the complexity of managing multiple disparate solutions, streamlining operations for IT teams. It thus becomes more appropriate for contemporary cloud-based applications.

Conventional firewalls mainly focus on intrusion detection-prevention, packet filtering, and stateful inspection in order to secure the network perimeter. They achieve this by enforcing rule-based traffic restrictions against illegitimate users. They frequently demand that users connect via proxies or VPNs, which can add complexity and latency. Traditional firewalls can be limited in flexibility. In terms of adaptive security, they may lack the agility needed to adapt to rapidly changing security threats or organizational needs. They often involve multiple distinct solutions for various security tasks. This led to fragmented management and increased costs. Firewalls are often managed independently, which leads to complexity and potential inconsistencies.

They may require manual integration with other security components. Traditional firewalls can be deployed as physical appliances, virtual appliances, or in hybrid configurations. This flexibility can be beneficial but often results in higher maintenance and operational costs. Integration challenges can be another issue. Using traditional firewalls may come with challenges when integrating new security technologies or adapting to cloud environments due to the reliance on legacy systems. The mentioned differences are going to be addressed and the following topics are going to be covered in this article.

• What is SASE?

  • What is SASE security?

• What is Firewall?

• What are the common types of Firewalls?

  1. Next-Generation firewall (NGFW)

  2. Network Firewall

  3. Internal Firewall

  4. Packet Filtering Firewall

• Is Firewall still necessary?

• What is the primary difference between SASE and a traditional firewall?

  • How do SASE and firewalls handle security differently?

  • Can SASE replace traditional firewalls?

• What are the advantages of SASE over traditional firewalls?

  • When should an organization choose SASE over a firewall?

  • How does the deployment of SASE differ from that of a traditional firewall?

What is SASE?

SASE is primarily a cloud-based wide-area network security solution. SASE positions the cloud at the heart of the network, not the physical main data center. As more businesses transition to SaaS and other cloud-native apps, the boundaries of the network are getting wider. This includes almost all places where a network user may be found. By installing security agents on their device, SASE can be utilized to secure a single, isolated user. At the network edge, where users congregate in groupings like branches of an enterprise, a client device could be required as a freeway to the cloud's nearest edge data center or the central cloud. This onslip must possess sufficient intelligence to arrange branches and transfer the main workload to the cloud. SASE replaces a patchwork of traditional network and security components, including:

• WAN Optimization: SASE incorporates WAN optimization features to improve network performance and reduce latency.

• Firewall: SASE replaces traditional firewalls by providing integrated perimeter security.

• MPLS Networks: Many organizations are moving away from expensive Multiprotocol Label Switching (MPLS) connections in favor of more flexible SD-WAN solutions that can be integrated with security services.

• Traditional VPNs: SASE offers secure remote access capabilities and eliminates the need for VPN concentrators. Instead of relying on virtual private networks that backhaul traffic to corporate data centers, SASE provides direct, secure access to applications from any location.

• Point Security Solutions: Legacy models often require multiple standalone solutions for firewall, web filtering, and access control. SASE consolidates these into a single cloud-delivered service, reducing complexity and cost.

• Cloud Access Security Broker (CASB): SASE includes CASB functionality to protect cloud applications and data.

• Secure Web Gateway (SWG): SASE incorporates SWG capabilities to filter and control web traffic.

What is SASE security?

Access control and safety measures in the private infrastructure cannot rely on traditional hardware appliances since a large number of users and apps no longer reside on and function on a physical server. It is currently not accurate that users and applications would be within the network boundary, as was assumed by traditional security procedures. IT businesses need to be agile in order to take advantage of novel revenue streams. This is crucial as a result of the shifting of corporate data to the cloud, people working from distant locations, and digital transformation projects. The old network perimeter is therefore collapsing, necessitating the development of new models for threat, data, and access management. Organizations are discovering that in a world where the cloud is the primary technology, their current assortment of stand-alone point solutions are no longer enough. SASE offers a complete security solution that expands traditional perimeter-based protection. It comes with a bunch of security capabilities for users, devices, and applications. Key SASE security features include Zero-Trust Architecture and Cloud Access Security Broker (CASB). SASE includes Secure Web Gateway (SWG) capabilities to filter and control web traffic. SWGs have the ability to uphold internet utilization regulations, ban harmful sites, and stop malicious software installations. Advanced Threat Protection (ATP) tools are included with SASE to identify and stop advanced threats. These include ransomware, phishing, and zero-day attacks. SASE assists in preventing the exfiltration or misuse of sensitive data. DLP features can identify and block unauthorized data transfers. SASE can integrate with endpoint security solutions to protect devices from malware and other threats, including vulnerability detection.

SASE provides traditional network security functions, such as firewall, VPNs, and intrusion detection. Through cloud-delivered services, SASE security offers to provide the required networking and security capabilities. Legacy solutions and appliances dependent on perimeters are eliminated in a SASE approach. Users connect to the SASE cloud service to securely access and use online services, applications, and data with the persistent implementation of security rules, as opposed to sending traffic to an appliance for security. The worldwide network that the cloud provider runs on its hardware is referred to as the edge in SASE. From any location, users can access cloud services by checking in and verifying their identities. They are then routed through this edge into cloud territory.

What is a Firewall?

Firewall is a network traffic restriction system, which is employed to limit access to, from, and within private networks. The way this software works is by permitting or blocking certain data packages. Usually, its goal is to deter malevolent conduct and stop anyone from participating in illegal online activities. This is what is going to happen whether they are inside or outside of a private network. A firewall is a system that is hardware, software, a software-as-a-service (SaaS), a public or private (virtual) cloud, or a specialized combination of hardware and software units. In a private network, firewalls operate as controlled borders or gateways to control the flow of authorized and unauthorized web traffic. Network security firewalls are utilized for web traffic control and are usually employed to impede the propagation of potential dangers. Firewalls direct web traffic through checkpoints where it is examined using already set parameters and handled. Typically, a private network's or its host device's borders are gated using firewalls. Firewalls are therefore a type of security solution that falls within the larger umbrella of access for user control. Usually, these barriers are configured on either the user's PC and other hosts or on dedicated network equipment. Essentially, firewalls act as gatekeepers, as they examine every network packet and determine whether to let or restrict it in accordance with pre-set rules.

Modern next-generation firewalls (NGFWs) offer a number of features to improve network security in addition to these fundamental capabilities. These consist of URL filtering, malware defense, intrusion detection and prevention, application visibility and control, deep packet inspection, and more.

What are the Common Types of Firewalls?

Various types of firewalls cater to different security needs and environments. These firewall types are going to be mentioned in detail in the next chapter. The common types of firewalls are listed below.

1. Next-generation firewall (NGFW)

2. Network firewall

3. Internal Firewall

4. Packet filtering firewall

1. Next-Generation Firewall (NGFW)

A security appliance known as a next-generation firewall (NGFW) analyzes network traffic and implements rules to prevent potentially harmful traffic. NGFWs enhance and expand upon the capabilities of traditional firewalls. They carry out every task that firewalls do, but they are more powerful and have more functionality. Every feature that a standard firewall has, an NGFW also has. These include packet filtering, VPN recognition, stateful inspection, recognition and management of applications, intrusion detection, risk assessment, adapting to changing security risks, etc. NGFWs employ packet filtering along with deep packet inspection, or DPI.

2. Network Firewall

Hardware or software that limits and allows network traffic flow is called a network firewall. By enforcing rules that prevent unauthorized traffic from reaching a secure network, network firewalls aid in the prevention of cyberattacks.

The purpose of network firewalls is to restrict network traffic flow. They are frequently used as a barrier between an Internet-like network and a private network that has a distinct security posture. A secure private network may have network firewalls installed throughout it to lower the danger of cyberattacks and stop illegal access to confidential data. In addition to monitoring and filtering internet traffic, network firewalls include sophisticated capabilities like automation, connectors, and sandboxing to enhance security. Incorporating threat intelligence to prevent advanced cyberattacks, modern firewalls can be deployed in virtual environments to safeguard cloud data and distant branches.

3. Internal Firewall

An internal firewall is a type of security measure used to thwart intrusions on a network that have already passed the perimeter. An internal firewall, as opposed to a conventional perimeter firewall, needs to be quick enough to meet the demands of internal traffic while proactively providing visibility and protection against insider threats. The likelihood of cyberattacks nowadays surpassing the network perimeter is growing, and internal firewalls reduce the amount of harm that may be caused by them. Large organizations with numerous network segments serving distinct departments and networks with broad attack surfaces from distributing services across public and private clouds will find internal firewalls very helpful. Internal firewalls employ micro-segmentation to reduce the attack surface. This creates discrete, separately secured zones within the network. They leverage smart automation to apply and update security policies depending on typical network behavior.

An internal firewall uses a deeper awareness of internal traffic to identify activity that deviates from what admins expect to see. They don't attempt to identify and neutralize each threat individually. It creates policies to mitigate threats that use numerous attack vectors at the network and process levels. Positioned at key locations within the internal network, an internal firewall applies a zero-trust strategy to isolate attacks and minimize possible harm. It stops threats from moving since it assumes they have already entered. Internal firewalls are deployed within a network to segment it into smaller, more secure subnets. Some common use cases for internal firewalls are listed below.

• Segmenting Sensitive Data: Internal firewalls can be used to isolate critical systems, such as databases, servers, and financial applications, from less sensitive parts of the network. They can restrict access to sensitive data based on user roles, departments, or other criteria.

• Preventing Malware Spread: If a malware infection occurs, internal firewalls can help contain the spread by limiting the infected system's access to other parts of the network. Firewalls can be used to isolate compromised systems until they can be cleaned and restored.

• Improving Network Performance: Internal firewalls can help reduce network congestion by limiting traffic between certain subnets.

• Implementing a DMZ: They can be employed to protect public-facing services. Internal firewalls can be used to create a demilitarized zone (DMZ) to protect public-facing services, such as web servers and email servers, from attacks.

4. Packet Filtering Firewall

In the OSI model, packet-filtering firewalls function at Layer 3, the network layer. Network addresses, ports, or protocols are the basis for processing decisions made by packet-filtering firewalls. Packet-filtering firewalls operate quickly as their decisions are made with little to no reasoning. They don't conduct any internal traffic inspections. Another reason for this is not keeping any state data. Every type of traffic that passes past the firewall requires manual port opening. Firewalls that use packet filtering are seen as being less secure. This is so that any traffic flowing on a port that has been authorized can be forwarded by them. Therefore, malicious traffic may be sent, but it won't be banned as long as it's on a port that is allowed. Some use cases of packet filtering firewalls are given below.

• Protection against IP spoofing attacks, in which the firewall looks up incoming packets' source IP addresses. The firewall can stop attackers from posing as authorized users on the network by making sure the packets come from reliable and expected sources. This is crucial for perimeter defenses in particular.

• To control and optimize the flow of network traffic. These firewalls provide the ability to restrict traffic between various subnets within the company by configuring rules that correspond to network policy. Traffic between subnets can be limited to help contain possible breaches and segment network resources based on sensitivity levels or departmental needs.

• Packet filtering firewalls process traffic fast and with minimal overhead since they are less computationally demanding.

Is a Firewall still necessary?

Yes. A Firewall is still necessary and crucial. Although the protection improves when migrating to the cloud, it's obviously not exhaustive. Information and communication networks are under more purposeful threat than at any other time in history. Malicious actors have hijacked new technologies that susceptible organizations developed and used as a form of defense for their own evil purposes. As technology has become more widely used by the public, attack surfaces have expanded, necessitating the need for an effective security solution. The topic of how to firewall our environments is more important than whether to do so. Firewall security, which guards your network's perimeter and internet access, is still crucial. But the definition of a network perimeter is becoming more hazy with the advent of home offices, vast internet access, and so on. Protection is still necessary for your internet access, network perimeter, which may be worldwide in scope, and public, private, or hybrid cloud environments. A next-generation firewall is the most straightforward option that fulfills all of your requirements.

Network security systems need to be present in several states, currently. The function of the firewall has expanded along with the complexity of networks. Personnel and organizations must access a network from a variety of locations and methods, including maybe the fictitious "cloud", due to modern business practices. Even when they are working with organizations outside of their network, users are nonetheless protected to the same extent. Prominent industry players label this transition from perimeter to multiple micro-perimeters.

What is the primary difference between SASE and a traditional firewall?

The main differences between SASE and traditional firewalls are their architecture, functionality, and approach to network security. The following table provides the main differences between SASE and a traditional firewall.

Feature	SASE	Firewall
Deployment Model	Cloud-native architecture, delivered as a service	Typically on-premises or hybrid solutions
Security Coverage	Integrates multiple security functions (e.g., ZTNA, SWG, DLP)	Primarily focuses on perimeter security
Adaptability	Highly adaptable to changing business needs	Less adaptable; often requires hardware upgrades
Management	Centralized management through a single platform	Management can be complex due to multiple systems
Scalability	Easily scalable with no physical hardware needed	Scaling requires additional hardware and resources
Core Components	Combines SD-WAN with security functions	Primarily consists of firewalls and related security appliances
Zero Trust Security	Built on Zero Trust principles, verifying every access request	Typically lacks comprehensive Zero Trust implementation
Network Optimization	Optimizes traffic routing for performance	Focused on filtering and controlling traffic
Threat Detection	Continuous monitoring and threat detection across the network	Relies on static rules and periodic updates
Flexibility	High flexibility to support remote and mobile users	Limited flexibility; primarily designed for static environments

Table 1. Differences between SASE and traditional firewalls

SASE integrates both networking and security services. This comes with a cloud-native architecture that supports the modern needs of an enterprise. The integration brings capabilities like Zero Trust security, where every user and device is continuously verified before accessing resources.

Traditional firewalls primarily focus on perimeter security. They rely on hardware-based solutions that create a defined boundary around the network. These solutions typically involve multiple standalone appliances that can be cumbersome to manage and scale. Traditional firewalls are often limited in their ability to adapt to the dynamic requirements of today's remote work environments and the cloud.

SASE's architecture incorporates SD-WAN. It is useful to optimize network performance with no security downgrade. SASE utilizes edge computing principles. It can deliver secure access from anywhere. It can improve user experience and reduce latency. This is a stark contrast to traditional models that may require traffic to be routed back through centralized data centers for inspection, leading to increased latency.

How do SASE and firewalls handle security differently?

The following table provides a comparison of SASE and firewalls in security management and different approaches to security.

Aspect	Secure Access Service Edge(SASE)	Traditional Firewalls
Focus	Integrates security with WAN capabilities, offering a holistic approach to network security.	Primarily focuses on perimeter security and traffic filtering.
Deployment	Cloud-based, enabling scalable and flexible security solutions.	Can be on-premises or cloud-based, often requiring physical hardware.
Security Perimeter	Decentralized, allowing secure access from any location or device.	Centralized around a defined network boundary.
Traffic Inspection	Inspects traffic at the nearest points of presence (PoP), enhancing performance.	Requires remote users to connect via VPNs or proxies for inspection.
Security Services	Comprehensive (threat detection, data protection, access control, user authentication).	Limited (packet filtering, intrusion detection, VPN tunneling)
Network Optimization	Global optimization	Limited optimization

Table 2. How do SASE and Traditional firewalls handle security

SASE comes with a complete security framework. This comes in handy for adaptive responses to new threats. Traditional firewalls typically focus on specific functions like packet filtering and intrusion detection. They mostly require more than one solution to handle security needs. In terms of network performance, firewalls can impact when handling large volumes of traffic. This makes SASE particularly well-suited for modern enterprises that require flexibility and scalability in cloud and remote work. Types of security services offered by both SASE and firewalls are outlined below.

SASE security services

SASE security services are as follows:

• Cloud Security provides secure access to data and apps from any location.

• Zero Trust enforces context-based policies and identity for access.

• Data Loss Prevention (DLP) protects sensitive data.

• Secure Web Gateway (SWG) filters internet traffic from malware.

• Cloud Access Security Broker (CASB) manages security policies for cloud services.

Firewall Security Services

Firewalls act as a barrier between a trusted network, like a corporate network, and an untrusted network, like the Internet. Traditional firewalls are typically deployed on-premises and require hardware and maintenance. Firewalls offer a more limited set of security services compared to SASE, typically focusing on the following security functionalities:

• Packet filtering blocks or lets network traffic based on predefined rules. It inspects packets based on header information.

• Intrusion detection identifies and responds to potential security threats.

• VPN tunneling creates secure connections between remote users and the corporate network.

• Threat detection monitors network traffic for threats.

• Access control regulates user access with rules.

• Intrusion Prevention Systems (IPS) identify and block potential threats in real-time.

Can SASE replace traditional Firewalls?

Yes, SASE can replace traditional firewalls in modern organizations. SASE's cloud-native architecture, integrated security services, and distributed workforces make it a compelling tool. Here are some scenarios where SASE might be a better fit.

• SASE can provide secure and consistent access to network resources for remote work. No need for complex VPN configurations.

• For those who rely on cloud-based applications and services, SASE can offer a unified security platform and reduce complexity.

• While SASE can generally replace traditional firewalls, there may be cases where legacy systems or specific compliance requirements need traditional firewalls. A hybrid approach may be necessary and bring together SASE and firewalls.

In some cases, a hybrid approach may be the most suitable solution. It combines SASE with traditional firewalls to address specific security needs. This can be particularly beneficial for complex security environments or legacy systems that require additional protection.

What are the advantages of SASE over traditional firewalls?

SASE comes with a modern approach to network security. The key advantages of SASE compared to traditional firewalls are listed below.

• Scalability: SASE easily scales to accommodate growing numbers of users and devices, particularly in cloud environments. This flexibility leads to quick adaptation to demand. Traditional firewalls mostly require significant investment and complexity to expand capabilities in growth or transition.

• Comprehensive Security: SASE combines multiple security functions into one framework. These include threat detection, data protection, access control, and user authentication. This complete approach lets all aspects of security be covered regardless of user location.

  Traditional firewalls primarily focus on perimeter defense, which leaves remote users and cloud applications out of complete security. Traditional firewalls offer a more limited set of security services, typically focusing on packet filtering and intrusion detection. They offer fragmented security and need additional solutions to cover the vulnerabilities.

• Simplified Management: SASE solutions are centrally managed and often come with intuitive user interfaces. They centralize management through a single interface. This reduces the complexity associated with managing multiple security tools and policies. This simplification enables faster updates and consistent policy enforcement across the network.

  Traditional firewalls require the management of various hardware and software components. They can be complex to manage and require specialized knowledge and skills. This can increase operational costs and the risk of misconfigurations.

• Better Support for Remote and Mobile Users: SASE is designed with remote work in mind. It serves secure access from any location or device without relying on traditional VPNs or backhauling traffic through central data centers. Traditional firewalls typically struggle to provide adequate support for mobile and remote users due to their perimeter-centric model. This is sometimes the reason for bottlenecks and latency issues when accessing the cloud.

What are the drawbacks of traditional firewalls?

While traditional firewalls have been foundational in network security, they exhibit several limitations:

• Limited Cloud Compatibility: As organizations increasingly adopt cloud services, traditional firewalls often fail to integrate effectively, necessitating additional solutions for comprehensive coverage.

• Complexity in Managing Distributed Networks: The need for multiple-point solutions complicates management, making it difficult to maintain consistent security policies across diverse environments.

• Perimeter-Centric Approach: This model is less effective in today's decentralized landscape where users access resources from various locations, leaving significant gaps in security coverage.

When should an organization choose SASE over a Firewall?

When deciding whether to implement SASE or stick with traditional firewalls, several factors have to be taken into account. These include cloud adoption, workforce distribution, existing infrastructure, and long-term IT strategy. When deciding between a firewall and a SASE, it is important to take the following factors into account.

• Remote Work Trends: Assess the extent of remote or hybrid work needed. SASE is designed to provide secure access for users in distributed workforces.

• User Mobility: SASE’s ability to enforce security policies consistently at all endpoints is its powerful side.

• Evaluate Current Cloud Usage: Determine how extensively your organization utilizes cloud services. If your applications are primarily cloud-based, SASE offers a cloud-native architecture that enhances security and performance across distributed environments.

• Future Cloud Plans: Consider future plans for cloud adoption. If transitioning to a cloud-first strategy, SASE may be more suitable due to its integrated security and networking capabilities.

• Integration Complexity: Consider the complexity of integrating new solutions with existing systems. SASE simplifies management and reduces the need for complex integrations.

• Current Security Solutions: Review your existing firewall and security infrastructure. If you already have robust on-premises firewalls but require enhanced cloud security, a hybrid approach might be beneficial—leveraging both traditional firewalls and SASE.

• Growth Projections: Analyze your organization’s growth projections. SASE provides greater scalability compared to traditional firewalls, making it easier to adapt as your organization expands or changes.

• Resource Allocation: With SASE, organizations can allocate IT resources more efficiently as it reduces the overhead associated with maintaining multiple security appliances.

• Consistency Across Environments: Determine how critical it is for your organization to enforce consistent security policies across all environments. SASE excels in this area by providing uniform policy enforcement.

• Compliance Requirements: Evaluate any requirements in compliance that may need specific security measures. Traditional firewalls may still be necessary for those who have stringent compliance needs and needs to inspect and control traffic in detail.

• Maintenance and Updates: Consider the maintenance burden of each option. Traditional firewalls often require regular updates and manual maintenance, while SASE solutions are managed in the cloud, reducing the operational load on IT teams.

• Strategic Goals: Align your choice with long-term IT strategies. If your strategy emphasizes digital transformation and agility, SASE aligns well with these goals by providing flexible and scalable solutions.

How does the deployment of SASE differ from that of a traditional Firewall?

The deployment of SASE significantly differs from that of traditional firewalls. The reason is cloud-native architecture and its implications for scalability, maintenance, updates, and policy enforcement. SASE is inherently designed for cloud deployment. Traditional firewalls typically require on-premises deployment, and hardware installations can limit flexibility and scalability.

The scalability of SASE is a key advantage over traditional firewalls. Security services can be set to changing demands without the need for additional physical hardware. Rapid scaling and fluctuating user loads are handled more easily. Traditional systems often involve complex upgrades and expansions.

SASE simplifies maintenance by centralizing security management in the cloud. Organizations benefit from reduced operational complexity. Traditional firewalls require ongoing maintenance of physical devices, including regular updates and patches, which can be resource-intensive and prone to human error.

With SASE, updates can be deployed automatically across the entire network without downtime or manual intervention. This ensures that all users are protected with the latest security measures in real time. Traditional firewalls often necessitate manual updates, which can lead to inconsistencies in security posture if not managed diligently.

SASE enables consistent policy enforcement. It employs a zero-trust model. Traditional firewalls often rely on perimeter-based security models. They may not effectively address the complexities of modern distributed work environments.

Because SASE comes with a cloud-native nature, it dynamically adjusts policies based on real-time context like user behavior or device state. This is an expansion in security compared to what traditional firewalls can maintain. Traditional systems typically apply static rules that may not account for the nuances of user behavior or changing threat types.