# SD-WAN and SASE
One-sentence definition: SD-WAN steers traffic over multiple underlays; **SASE** converges networking with cloud-delivered security.
## Key Facts
- SD-WAN: path selection, QoS, overlay encryption, centralized policy.
- SASE: integrates SWG/CASB/ZTNA/FWaaS/DLP at cloud edge.
- Secure the controller, certificates, and device provisioning (ZTP).
- Validate segmentation per app; measure latency/Jitter for SLA.
- **Verify:** check official (ISC)² CBK and current exam outline.
## Exam Relevance
- Pick SASE to apply security policy close to users anywhere.
**Mnemonic:** “**Steer** smart, **secure** everywhere.”
## Mini Scenario
Q: Branch to SaaS traffic hairpins to HQ—solution?
A: SD-WAN with local breakout + SASE inspection.
## Revision Checklist
- SD-WAN vs SASE.
- ZTP security.
- Overlay encryption.
## Related
[[Zero Trust Network Access (ZTNA)]] · [[Proxies and Secure Web Gateways]] · [[VPN Basics (SSL TLS vs IPsec)]] · [[DDoS Attacks and Defenses]] · [[TLS Handshake Overview]] · [[Domain 4 - Index]]