Legacy Network vs SASE: Why Cato’s Converged Architecture Replaces MPLS and Firewall Appliances

The Legacy Network Dilemma

How MPLS, Firewalls, and VPNs Shaped Enterprise Networking

For decades, enterprise networks were defined by a rigid, perimeter-based approach. The standard toolkit included  MPLS circuits  for reliable branch connectivity,  on-premises firewalls  for perimeter security,  VPN concentrators  for remote access, and a  hub-and-spoke topology  that funneled all traffic through a central data center. This model assumed that users, applications, and data were static and resided within the corporate perimeter.
 

In this environment,  MPLS provided predictable, high-quality connections  between sites, while firewalls enforced security at the network edge. VPNs extended access to remote users, but always through the same centralized control points. This architecture was manageable when employees worked from fixed offices and applications were hosted on-premises.

However, the world has changed.  Cloud adoption, SaaS proliferation, and hybrid work  have dissolved the traditional perimeter. Users now connect from anywhere, and applications live in multiple clouds. The legacy model, built for a static, centralized world, is now a barrier to agility and innovation.

The Pain Points: Fragmentation, Complexity, and Cost

The legacy approach is  appliance-heavy and operationally fragmented . Each branch requires its own stack of hardware—firewalls, routers, WAN optimizers—leading to inconsistent security enforcement and complex management. Bringing a new site online means provisioning MPLS, shipping appliances, and configuring policies, often taking weeks or months.
 

Key operational pain points include:

•  Fragmented security policies:  Each appliance enforces its own rules, creating gaps and inconsistencies.
•  Expensive backhauling:  Branches often send internet-bound traffic to a central data center for inspection, increasing latency and WAN costs.
•  Hardware refresh cycles:  Appliances require regular upgrades and replacements, adding to capital and operational expenses.
•  Long deployment times:  Provisioning new sites or responding to business changes is slow and resource-intensive.

As organizations expand globally, adopt cloud services, and support remote work, these challenges multiply. The legacy model cannot keep pace with the demands of a modern, distributed enterprise.
 

Why Legacy Models Fail in the Cloud-First, Hybrid Era

Cloud Migration and the Static Perimeter Problem

Cloud migration exposes the limitations of perimeter-based networking. Applications and data now reside in  public clouds, SaaS platforms, and distributed data centers . Legacy networks, designed to route all traffic through a central hub, create bottlenecks and degrade performance for cloud-bound traffic.

For example, a user in Singapore accessing a SaaS application may have their traffic routed through a corporate data center in London for security inspection. This "hairpinning" adds latency, increases costs, and undermines the user experience.

Hybrid Work and the Challenge of Anywhere Access

The rise of  hybrid and remote work  has exposed the weaknesses of VPNs and perimeter-based security. VPNs were never designed for large-scale, always-on remote access. As more users connect from home or on the road, VPN concentrators become chokepoints, causing slowdowns and dropped connections.

Traditional security models grant broad access based on network location. Once authenticated, users often have access to more resources than necessary—a risky proposition in the age of phishing, ransomware, and insider threats.

Global Expansion and the Limits of Appliance Sprawl

Global expansion magnifies the challenges of legacy networking. Opening new branches requires  shipping hardware, provisioning MPLS circuits, and configuring appliances  at each location. This process is slow, costly, and difficult to scale. Managing hundreds of distributed firewalls and routers becomes a logistical nightmare, especially when IT resources are centralized or limited.

Enter SASE: The Unified, Cloud-Native Alternative

What Is SASE? Core Components and Architecture

 Secure Access Service Edge (SASE)  is a cloud-native architecture that converges networking and security into a single, unified service delivered from the cloud. SASE is designed for a world where users, devices, and applications are everywhere.
 

Core SASE components include:

•  SD-WAN: Software-defined WAN replaces rigid MPLS with intelligent routing over the internet or private backbones.
•  SWG (Secure Web Gateway):  Protects users from web-based threats with advanced filtering and threat prevention.
•  CASB (Cloud Access Security Broker):  Provides visibility and control over cloud application usage, ensuring data protection and compliance.
•  ZTNA (Zero Trust Network Access):  Enforces least-privilege access based on user identity and context, continuously verifying trust.
•  FWaaS (Firewall-as-a-Service):  Delivers scalable, cloud-native firewall protection without hardware appliances.

SASE platforms are  cloud-native, globally distributed, and managed centrally , enabling organizations to enforce consistent policies, scale elastically, and support users and applications anywhere.

SASE vs. Legacy: A Feature-by-Feature Comparison
 

Cato’s Converged Architecture: The Strategic MPLS and Firewall Replacement

How Cato Unifies Networking and Security

Cato Networks delivers a converged SASE platform that replaces the patchwork of MPLS, NGFW, VPN, and SD-WAN with a single, cloud-delivered service. All traffic—branch, remote, cloud, and mobile—flows through Cato’s global network of  Points of Presence (PoPs) , where it is inspected, routed, and secured in real time.

Key benefits:

•  Elimination of appliance sprawl:  No more shipping, installing, or managing hardware at every site.
•  Unified policy enforcement:  Security and access policies are defined once and enforced everywhere, reducing gaps and inconsistencies.
•  Seamless support for hybrid and remote work:  Users connect securely from anywhere, with the same level of protection as in the office.

Private Global Backbone: Performance and Reliability

Unlike SD-WAN solutions that rely on the public internet, Cato operates a  private global backbone  connecting its PoPs. This backbone is engineered for low latency, high availability, and optimized routing, delivering  MPLS-like performance  without the cost or rigidity of legacy circuits.

•  Reduced latency:  Traffic takes the shortest, most efficient path between users and applications, whether in the cloud or on-premises.
•  Minimized packet loss:  The private backbone avoids congestion and instability common on the public internet.
•  Consistent user experience:  Applications perform reliably, even for global and mobile users.

Centralized Policy and Single-Pass Security

Cato’s single-pass engine  inspects traffic once for all security functions—firewall, threat prevention, data loss protection, and more. This approach reduces processing overhead, accelerates performance, and ensures that security is always enforced, regardless of where users connect.

•  Centralized management:  IT teams define policies in one place, with instant propagation across the entire network.
•  Continuous verification:  Zero Trust principles ensure that access is always based on identity and context, not just network location.
•  Simplified compliance:  Unified logging and reporting make it easier to demonstrate compliance with regulatory requirements.
   

Real-World Scenarios: The Cato Advantage

Global Branch Networks: Rapid Onboarding and Consistent Security

A global retailer with over 300 stores worldwide faced mounting MPLS costs and inconsistent security enforcement. By adopting Cato’s SASE platform, they replaced MPLS with Cato’s private backbone, onboarded new sites in days (not weeks), and enforced uniform security policies across all locations. The result: lower costs, faster expansion, and reduced risk.

Mobile Users: Seamless, Secure Access from Anywhere

A financial services firm with 60% of its workforce remote struggled with VPN bottlenecks and security gaps. Cato enabled direct, secure access to cloud and on-premises applications for all users, regardless of location. Centralized policy enforcement and continuous verification ensured that every connection was secure, reducing the risk of breaches and improving user productivity.

Multi-Cloud and SaaS: Unified Visibility and Control

A SaaS provider operating across AWS, Azure, and Google Cloud needed unified access and security controls. Cato’s platform provided a single pane of glass for managing policies, monitoring traffic, and enforcing compliance—eliminating the need for multiple firewall appliances and manual policy mapping.

Operational and Strategic Benefits for IT Leaders

Simplified Management and Reduced Overhead

By consolidating networking and security into a single platform, Cato reduces the number of tools, vendors, and processes IT teams must manage. This leads to:

•  Faster deployments:  New sites and users can be onboarded in minutes, not months.
•  Lower operational costs:  No more hardware refresh cycles, patch management, or on-site troubleshooting.
•  Improved visibility:  Centralized monitoring and reporting provide real-time insights into network and security posture.

Agility, Scalability, and Future-Readiness

Cato’s cloud-native architecture enables organizations to adapt quickly to changing business needs:

•  Scale elastically:  Add users, sites, or capacity without worrying about hardware limits.
•  Support innovation:  Enable cloud migration, SaaS adoption, and hybrid work without compromising security or performance.
•  Stay ahead of threats:  Continuous updates and threat intelligence ensure that security is always current.
   

Conclusion: The Cleanest Path to Modernization

Legacy networks—built on MPLS, hardware firewalls, and fragmented point solutions—are no longer viable for cloud-first, mobile-first enterprises. They are costly, complex, and ill-suited to the demands of a distributed, dynamic world.

 Cato’s converged SASE architecture offers a strategic, future-proof alternative.  By unifying networking and security in the cloud, Cato eliminates appliance sprawl, accelerates cloud adoption, and empowers IT leaders to deliver secure, high-performance connectivity to every user, everywhere.
 

For organizations seeking to modernize their networks, support hybrid work, and embrace the cloud with confidence, Cato represents the cleanest, most strategic path away from legacy sprawl—enabling agility, security, and scale for the digital era.
 

FAQ

How does SASE differ from traditional SD-WAN or VPN solutions?

SASE integrates networking and security in a single cloud-native platform, whereas SD-WAN and VPNs address only connectivity. SASE provides unified security, centralized management, and better performance for distributed and mobile users.
 

Can SASE really replace MPLS for global connectivity?

Yes. SASE platforms like Cato use a private global backbone to deliver MPLS-like performance with greater flexibility and lower cost, eliminating the need for expensive, rigid MPLS circuits.
 

How does Cato handle security for remote and mobile users?

Cato delivers security as a cloud service, enforcing policies consistently regardless of user location, and uses Zero Trust principles for continuous verification.
 

What are the operational benefits for IT teams?

SASE simplifies management by consolidating point solutions, automating policy enforcement, and reducing hardware dependencies, leading to faster deployments and lower operational overhead.
 

How does Cato’s single-pass engine improve security and performance?

Cato’s single-pass engine inspects traffic once for all security functions, reducing latency and processing overhead. This ensures comprehensive protection without sacrificing user experience.
 

What is the impact on compliance and audit readiness?

Centralized policy enforcement and unified logging make it easier to demonstrate compliance with regulatory requirements. Cato’s platform provides detailed reporting and continuous verification, simplifying audits.
 

How does Cato support multi-cloud and SaaS environments?

Cato provides unified access and security controls across all cloud platforms and SaaS applications, eliminating the need for multiple firewall appliances and manual policy mapping.
 

What are the cost implications of moving from MPLS to Cato SASE?

Organizations typically see significant cost savings by eliminating MPLS circuits, reducing hardware purchases, and streamlining management. Cato’s predictable, usage-based pricing further simplifies budgeting.
 

How quickly can new sites or users be onboarded with Cato?

New sites and users can be onboarded in days or even minutes, compared to the weeks or months required for legacy MPLS and appliance-based deployments.
 

How does Cato ensure consistent user experience for global and mobile users?

Cato’s private global backbone optimizes routing and minimizes latency, delivering reliable application performance and a consistent user experience, regardless of location.