Secure SD-WAN and Branch Transformation

Executive overview

Architected the migration from legacy MPLS-centric branch connectivity to a secure SD-WAN design with centralized policy, segmentation, and direct cloud access.

Business challenge

Branch connectivity depended on rigid, costly circuits with backhauled internet traffic, degrading cloud application performance. Network changes required per-site effort, and security policy varied across locations.

Environment and constraints

• Many geographically distributed sites with varying circuit availability.
• Cutovers constrained to defined maintenance windows.
• Coexistence with legacy WAN during the transition period.

Objectives and success measures

• Decouple branch connectivity from any single transport provider.
• Deliver consistent, centrally managed security policy to every site.
• Improve performance for cloud-hosted applications.

Role and responsibilities

Network architect responsible for target design, security integration, migration sequencing, and vendor coordination.

Architecture and design approach

• Defined a standardized branch reference architecture: transport-independent overlays, centralized policy, and local internet breakout with inspection.
• Integrated segmentation so branch traffic classes remained separated end to end.
• Built a repeatable per-site migration template covering surveys, staging, cutover, and validation.
• Piloted at representative sites before scaling the rollout.

Security and governance considerations

• Direct internet breakout permitted only through inspected, policy-controlled paths.
• Segmentation preserved across the overlay for separated traffic classes.
• Configuration templates version-controlled and change-managed.

Implementation and migration approach

• Representative pilot sites validated the design against real traffic.
• Wave-based rollout with standardized runbooks and acceptance criteria.
• Fallback-to-legacy path retained until each site passed validation.

Key decisions and trade-offs

• Local internet breakout with cloud-delivered inspection rather than continued backhaul — better user experience with maintained inspection coverage.
• Template-first configuration model, accepting less per-site flexibility in exchange for operational consistency.

Results and outcomes

• Standardized branch connectivity onto a centrally managed overlay.
• Improved cloud application experience through local breakout with inspection.
• Reduced per-site change effort via template-driven configuration.
• Established consistent security policy across all locations.

Lessons learned

• Site surveys prevent most cutover surprises; skipping them saves days and costs weeks.
• A visible per-site scorecard keeps a long rollout accountable.

Related technologies

• SD-WAN platform
• Cisco routing and switching
• Next-generation firewalls
• Cloud security services
• Quality of service policy

Related projects