SD-WAN Network
Learning Workspace
Explore SD-WAN architecture, follow application traffic across multiple transports, investigate network failures, and understand how centralised policies influence routing and connectivity.
Interactive SD-WAN Topology Explorer
Explore the relationship between WAN edge devices, transport networks and encrypted overlay tunnels. Select a component to investigate its engineering role.
SD-WAN Underlay & Overlay Inspector
Investigate transport reachability, logical tunnels and controller connectivity. Compare the physical WAN with the SD-WAN control and data planes.
Transport & Tunnel State
| Component | Layer | State | Engineering Impact |
|---|
SD-WAN Fabric Health Dashboard
Investigate transport performance, overlay tunnel availability, SLA thresholds and application path selection. Introduce faults and trace how the SD-WAN responds.
Transport SLA & Tunnel Health
| Transport | Latency | Jitter | Loss | Tunnel | SLA |
|---|
Illustrative SLA for this application: latency ≤ 100 ms, jitter ≤ 30 ms, packet loss ≤ 1%. All three thresholds must pass for the path to qualify.
Application Path Investigation
Begin a trace to follow application traffic from Branch 1 to the Data Centre.
Learning Control Bar
Navigate five learning stages and track your progress across twelve SD-WAN engineering activities.
Unified SD-WAN Learning Dashboard
Track your progress across five learning stages and twelve interactive SD-WAN engineering activities. Continue from your next incomplete stage.
SD-WAN Learning Pathway
Understand the Fabric
Complete three interactive SD-WAN activities to understand network topology, transport and overlay architecture, and fabric health.
SD-WAN Topology Explorer
Underlay & Overlay Inspector
SD-WAN Fabric Health Dashboard
Stage 01 — Understand the Fabric
Before investigating application performance or diagnosing a WAN failure, establish how the SD-WAN fabric is built. Explore branch edges, WAN underlays, encrypted overlays, centralised control and the health signals that determine whether a transport can carry application traffic.
What You Will Investigate
- How branch sites connect through MPLS, Internet and LTE/5G transport networks.
- The difference between physical underlay reachability and logical overlay tunnel availability.
- How SD-WAN control-plane components influence fabric connectivity.
- How latency, jitter, packet loss and tunnel state affect application path eligibility.
Engineering Learning Objective
By the end of Stage 01, you should be able to distinguish underlay failures from overlay failures, interpret transport health, and explain why an application may move from one WAN path to another.
Three Interactive Engineering Activities
Complete each lab before advancingEngineering Investigation
Begin with the Topology Explorer to identify the network architecture. Next, use the Underlay & Overlay Inspector to separate transport failures from tunnel failures. Finally, examine the Health Dashboard to determine which available transport meets the example SLA thresholds and how the selected application path changes.
Stage 2
Stage 02 — Follow Application Traffic
An SD-WAN fabric can have several available transports, but not every path is equally suitable for every application. Follow application traffic from the branch, through policy classification and SLA evaluation, to the selected WAN transport and destination.
What You Will Investigate
- How SD-WAN identifies and classifies application traffic.
- How business intent and application policies influence path selection.
- How latency, jitter and packet loss affect SLA eligibility.
- How an alternative transport is selected when performance deteriorates.
- How forwarding decisions can be validated using path evidence.
Engineering Learning Objective
By the end of Stage 02, you should be able to trace an application flow through the SD-WAN fabric, explain why a specific WAN transport was selected, and identify when an SLA violation should trigger a different forwarding decision.
Three Interactive Engineering Activities
Follow the traffic investigation sequenceFollow the Application Decision
Use this five-step engineering workflow to understand how an application reaches its destination.
Engineering Investigation
Begin with an application traffic trace. Identify the source, destination and traffic class. Next, compare the available transport paths and their policy preferences. Finally, introduce an SLA violation and determine whether the application remains on its original path or moves to an alternative overlay tunnel. These examples use illustrative policy and telemetry values rather than measurements from a live SD-WAN deployment.
Application Traffic Investigation
Select an application, evaluate policy and transport health, then trace forwarding across the SD-WAN fabric.
Interactive SD-WAN Forwarding Topology
Classify
Policy
SLA
Forward
Verify
Select an application and begin the trace.
Application & Policy Inspector
EvaluatingEngineering Decision
The selected application is evaluated against transport availability, overlay tunnel state and application SLA thresholds.
Identify why a transport was selected and determine whether an underlay failure, tunnel failure or SLA violation changes the forwarding outcome.
Dynamic Path Selection
Compare MPLS, Internet and LTE/5G paths. Evaluate application policy, transport health and SLA compliance to determine the preferred forwarding path.
SD-WAN Candidate Path Evaluation
Select an application and inspect the preferred path.
Path Decision Inspector
EvaluatingApplication SLA Thresholds
Engineering Decision
Transport selection evaluates overlay availability, SLA compliance and application preference.
Reject paths with unavailable underlays, unavailable overlay tunnels or SLA violations. From the remaining eligible candidates, choose the first transport in the configured preference order.
Candidate Path Evidence
| Transport | Underlay | Overlay | Latency | Jitter | Loss | Decision |
|---|
SD-WAN SLA Performance Monitor
Examine latency, jitter and packet loss across the SD-WAN fabric. Compare synthetic telemetry against application SLA thresholds and investigate transport eligibility during network impairment.
Transport Telemetry Timeline
Inspect the telemetry charts and compare each metric with the application's SLA threshold.
Application SLA Inspector
EvaluatingCurrent Measurement
Engineering Interpretation
The monitor evaluates availability and application SLA compliance using synthetic transport telemetry.
A path is SLA compliant only when its underlay and overlay are available and latency, jitter and packet loss remain within the application's configured example thresholds.
SLA compliance determines path eligibility in this simplified model. The actual selected forwarding path also depends on application policy and preference order, as demonstrated in Lab 05.
All Transport SLA Comparison
| Transport | Underlay | Overlay | Latency | Jitter | Loss | SLA Result |
|---|
SD-WAN SLA Performance Monitor
Examine latency, jitter and packet loss across the SD-WAN fabric. Compare synthetic telemetry against application SLA thresholds and investigate transport eligibility during network impairment.
Transport Telemetry Timeline
Inspect the telemetry charts and compare each metric with the application's SLA threshold.
Application SLA Inspector
EvaluatingCurrent Measurement
Engineering Interpretation
The monitor evaluates availability and application SLA compliance using synthetic transport telemetry.
A path is SLA compliant only when its underlay and overlay are available and latency, jitter and packet loss remain within the application's configured example thresholds.
SLA compliance determines path eligibility in this simplified model. The actual selected forwarding path also depends on application policy and preference order, as demonstrated in Lab 05.
All Transport SLA Comparison
| Transport | Underlay | Overlay | Latency | Jitter | Loss | SLA Result |
|---|