Simple definition
SASE (Secure Access Service Edge) is an architecture that brings networking and security functions together in distributed services, commonly delivered from the cloud.
Technical definition
A SASE approach commonly combines WAN connectivity with security functions such as SWG, CASB, ZTNA, or firewall-as-a-service. Decisions use identity, context, destination, and policy rather than relying only on the local-network perimeter.
How it works / role
Traffic from a user, site, or endpoint is steered to a provider point of presence. Policies evaluate identity and context, apply security controls, and then forward traffic toward the Internet, a SaaS application, or a private resource.
What is it used for?
Provide consistent secure application access for distributed users and sites, including users outside the corporate network.
Practical example
A remote worker accesses a SaaS application through a SASE point of presence that applies ZTNA, web filtering, and data controls before allowing the session.
Common issues
- Excessive dependency on a provider or point of presence
- Traffic steering adds unnecessary latency
- Policies differ between remote users and branch sites
- Identity or device-posture integration is incomplete
Key takeaway: SASE is a network-and-security convergence architecture; success depends on routing and points of presence as much as on identity and security policy.