Secure Access Service Edge (SASE) has rapidly evolved into one of the most important architectural models for modern networks. Organizations transitioning to cloud applications, hybrid work models and distributed IT environments increasingly choose SASE because it combines network optimization with advanced cloud-based security. Despite its advantages, a SASE implementation is not a standard project, it requires careful planning, a phased approach and a clear understanding of the dependencies between network, identity, applications and security.
This article presents a practical step-by-step approach to implementing SASE, including challenges, risks and best practices.
Why Implement SASE?
SASE enables organizations to centralize, standardize and make their networking and security fully cloud-native. The main drivers include:
- Hybrid and remote work: users must be able to connect securely from anywhere.
- Cloud adoption: traffic increasingly bypasses the traditional data center.
- Modern threat landscape: Zero Trust and cloud security have become essential.
- Complexity reduction: fewer legacy hardware components, centralized management.
- Scalability: new locations can be added more quickly (fixed, mobile, temporary).
For environments that use multiple connection types, like fiber, Fixed Wireless Access, 5G, or satellite solutions such as Starlink, SASE provides a unified way to optimize and secure traffic.
A phased SASE implementation
1. Assess the current state
Evaluate:
- existing WAN topology
- connectivity types
- security appliances and VPN usage
- IAM structure
- cloud adoption
- locations and user groups
This assessment defines the roadmap.
2. Modernize WAN connectivity (SD-WAN)
In many implementations, SASE begins with SD-WAN because:
- traffic needs to be routed efficiently to the nearest SASE Points of Presence
- dynamic prioritization of applications is required
- organizations want flexibility between different connection types
- traditional MPLS structures are often too limited or costly
This often involves setting up a mix of wired and wireless connections, for example fiber combined with FWA or 5G.
3. Introducing Zero Trust Network Access (ZTNA)
ZTNA replaces traditional VPNs and forms the foundation of SASE. The transition typically follows these steps:
- Grant identity-based access
- Integrate with Identity Providers (e.g., Azure AD, Okta)
- Restrict access to specific applications
- Implement device posture checks
ZTNA can run in parallel with existing VPN solutions until the migration is complete.
4. Introduce cloud-delivered security services
In this phase, traditional security tools are gradually replaced by SASE services:
- Secure Web Gateway (SWG)
- Firewall-as-a-Service (FWaaS)
- CASB for SaaS monitoring
- DNS and web filtering
- DLP features
These services deliver consistent protection across all endpoints.
5. Centralizing policies
A SASE model is only effective if policies are managed centrally. This includes:
- Application-based policies
- Access and identity rules
- Segmentation policies
- Monitoring and logging
- Compliance requirements
Rolling out policies globally via the cloud ensures consistency.
Key Considerations and Challenges
1. Identity & Access Management must be flawless
SASE relies heavily on identity. If Identity Providers are not properly configured, risks may include:
- Overly broad access
- Inconsistent policies
- Missing MFA
- Incorrect role assignments
Investing in a strong identity foundation is essential.
2. Legacy Environments Require Additional Migration Steps
Some older applications are not designed for ZTNA, API access, or cloud authentication. This may require workarounds or modernization.
3. Performance Dependencies
SASE performance also depends on:
- Latency to the nearest PoP
- Quality of WAN connections (e.g., FWA during peak hours)
- Routing and application prioritization
- Cloud congestion
A robust SD-WAN layer minimizes these risks.
4. User Adoption
New access methods require clear communication to employees. Users need to understand why ZTNA works differently than a traditional VPN.
Best practices for a successful SASE implementation
1. Start Small, Scale Fast
Begin with a pilot group, often remote employees and then expand to additional sites and applications.
2. Use a Phased Migration Model
Introduce ZTNA, SWG, and FWaaS in stages to minimize risk.
3. Automate Where Possible
Automated policy deployment, identity synchronization, and performance monitoring accelerate adoption.
4. Monitor continuously
Use telemetry and analytics to detect anomalies and adjust policies accordingly.
5. Evaluate periodically
SASE is an ongoing process. Regularly review whether policies align with new applications, users, and emerging threats.
Conclusion
SASE is not a product that can be deployed all at once, but a strategic transformation of networking and security. By migrating in phases, managing policies centrally, and investing in identity, organizations can create a future-proof, scalable, and secure architecture. This approach benefits organizations in cloud-driven environments, hybrid work models, and situations where connectivity ranges from fiber to 5G and Starlink.
