Catch Advisors
Cybersecurity

What Is SASE? A Practical Guide for IT Leaders

SASE (Secure Access Service Edge, pronounced “sassy”) has become one of the most discussed acronyms in enterprise IT. Coined by Gartner in 2019, it describes a cloud-delivered architecture that converges wide-area networking and network security into a single service. But the marketing hype often obscures what SASE actually is and whether your organization needs it.

1. The Core Components of SASE

SASE is not a single product. It is an architectural framework that combines several technologies:

SD-WAN provides intelligent, application-aware routing across your wide-area network. It replaces or augments traditional MPLS connections with broadband, DIA, and LTE.

SWG (Secure Web Gateway) inspects and filters web traffic to block malware, phishing, and access to risky sites. It replaces on-premises web proxies.

CASB (Cloud Access Security Broker) provides visibility and control over SaaS application usage. It enforces data loss prevention policies and detects shadow IT.

ZTNA (Zero Trust Network Access) replaces traditional VPN with identity-based, least-privilege access to applications. Users get access to specific apps, not the entire network.

FWaaS (Firewall as a Service) delivers firewall capabilities from the cloud, eliminating the need for on-premises firewall appliances at every location.

2. Why SASE Exists

The traditional network security model assumed that users, applications, and data were inside the corporate perimeter. Firewalls and VPNs protected that perimeter. But three trends have rendered that model obsolete:

  • Cloud adoption: Applications have moved from on-premises data centers to SaaS and IaaS platforms
  • Remote work: Users connect from home, coffee shops, and airports, not just the office
  • Branch proliferation: Organizations with dozens or hundreds of locations cannot afford dedicated security hardware at every site

SASE addresses these trends by moving security enforcement to the cloud, close to the user and the application, regardless of location.

3. Who Needs SASE

SASE is most relevant for organizations that meet two or more of these criteria:

  • You have multiple office locations with aging firewalls and VPN concentrators
  • Your workforce is hybrid or remote and connecting through traditional VPN
  • You are heavy SaaS users with limited visibility into how employees use cloud applications
  • You are deploying or have deployed SD-WAN and want to integrate security into the same architecture
  • You are pursuing zero trust and need to replace VPN with identity-based access controls

If your organization is a single location with all on-premises applications and no remote workers, SASE is likely overkill.

4. Single-Vendor vs. Multi-Vendor SASE

One of the biggest decisions in SASE is whether to go with a single vendor that provides all components or to assemble best-of-breed solutions:

Single-vendor SASE (Cato Networks, Fortinet, Palo Alto Prisma Access) provides a unified platform with tight integration between networking and security. The tradeoff is that you are dependent on one vendor’s roadmap and capabilities across every component.

Multi-vendor SASE pairs an SD-WAN provider (VMware VeloCloud, Cisco Meraki) with a cloud security provider (Zscaler, Netskope). This approach lets you pick the best solution in each category but adds integration complexity.

There is no universally correct answer. Single-vendor is simpler to manage. Multi-vendor may deliver stronger capabilities in specific areas.

5. Common Mistakes to Avoid

Do not treat SASE as a product purchase. It is an architecture shift that affects networking, security, and operations teams. Plan for organizational change, not just technology deployment.

Do not rip and replace everything at once. Most successful SASE deployments are phased. Start with SD-WAN, add SWG and ZTNA, then layer in CASB and FWaaS over 12-18 months.

Do not skip the assessment. Understand your current network topology, security posture, application landscape, and user access patterns before selecting a SASE provider.

6. Getting Started

If SASE is on your radar, start with these steps:

  1. Audit your current stack: Document every firewall, VPN, proxy, and WAN circuit across all locations
  2. Map your users and applications: Where do people work, and what do they need to access?
  3. Define your zero trust maturity: How far along are you in moving from perimeter-based to identity-based security?
  4. Evaluate 3-4 providers: Score them against your specific requirements, not generic feature lists

Considering SASE for your organization? Get a free assessment and we will help you evaluate whether SASE is the right architecture for your needs.